Biology Flashcards

Question

1. What does smooth muscle do, as part of the muscular tissue group? 2. What does it look like? 3. Is it voluntary or involuntary? 4. Where is it located?

Answer 1

1. - Churning and mixing action of the stomach - Propulsion of food along the GI-Tract - Contraction of uterus during childbirth - Vasodilation/ constriction of blood vessels 2. - Lacks striation - fusiform - layered - single nucleated 3. Involuntary 4. Forms layers in the walls of digestive, respiratory and urinary tracts, blood vessels, uterus etc.

Answer 2

1. - Makes up the heart, thick muscles of the heart contract to pump blood out, then relax to let blood in - specialised muscle tissue that has properties of both smooth muscle and skeletal muscle 2. Striated and branched 3. Involuntary 4. Localised to the heart 5. Myoctyes are joined together via intercalated discs, cardiac muscle does not fatigue easily

Answer 3

1. Neurons (nerve cells/ fibres) | 2. Neuroglia

Answer 4

Neurons (nerve cells/ fibres) | are excitable cells which generate and transmit nervous impulses

Answer 5

Neuroglia are the supporting cells - They provide structural framework - Protects and supports the neurons - Insulates neurons for better propagation - Unlike neurons, they don’t actually transmit electrical impulses directly

Answer 6

Nervous tissue is found in the peripheral nerves of the PNS throughout the body and organs of the CNS, the brain and spinal cord.

Answer 7

1. Simple epithelium - single layer of cells - all cells are in contact with the basement of the membrane - good for rapid diffusion 2. Stratified epithelium - two or more layers of cells, only the deepest layer sits on the basement membrane - good for protection (cells can be packed tightly together) (Pseudo stratified) - looks stratified but is actually simple

Answer 8

1. Simple squamous epithilium is a single layer of flat cells - very thin layer - cells are in direct contact with each other 2. It lines surface and inside of organs and body cavities - i.e lining of the air sacs of the lungs, lining of blood vessels, lining of heart chamber 3. Controls absorption and rapid diffusion

Answer 9

1. - Many layers for protection of underlying tissues. More durable than simple epithelium. - Basal cells are normally columnar or cuboidal and continually make new cells which are pushed towards the surface to replace the old ones. 2. Anywhere that acts as a protective layer, i.e nails, skin 3. Protection

Answer 10

-consists of few cells surrounded by an abundance of extra cellular material -highly vascular -contains lots of extra cellular matrix which are produced by cells -can vary from solid to fluid -solid extra cellular matrix- fibres (collagen, reticulum, elastin) Fluid extra cellular matrix- ground substance (water, glycosaminoglycans, proteoglycans, etc)

Answer 11

Each membrane consists of an epithelial sheet and an underlying connective tissue membrane that cover and protect other structures and tissues in the body. - mucous - serous - cutaneous - synovial

Answer 12

Lines inside cavities that open directly to external environment, e.g GI, respiratory, reproductive and urinary tract It secretes mucous which: - is a defence mechanism - traps dust/ pathogens - lubricates contents of GI tract

Answer 13

They line the cavities of the body that do not open to the external environment e.g lining of organs, the chest and abdominal cavities They secrete serous fluid which decreases friction between organs during movement

Answer 14

Found in the skin, it covers the entire body. It is many layers of keratinised epithelial cells which functions include: - protection - storage - sensation - temperature regulation, etc

Answer 15

1. Surrounds the synovial joint 2. Produces and secretes synovial fluid - lubricates joints - allows for frictionless movement - nourishes cells of the cartilage

Answer 16

Anatomy: Is the study of human body structures Physiology: is the study of the functions and activities performed by the body’s structures Histology: is the study of the tiny structures found in living tissue

Answer 17

Atoms are the smallest particle of material, also called chemical element, which still has the characteristics of that material.

Answer 18

Protons - found in the nucleus - positively charged - large in size Neutrons - found in the nucleus - neutral charge - large in size Electrons - orbits in shell around nucleus - negative in charge - small in size

Answer 19

Element: An element is a substance that is made entirely from one type of atom, therefore it will have exactly the same number of protons Molecule: A molecule however, is a group of atoms bonded together to form a chemical compound

Answer 20

- Hydrogen; forms organic compounds | - It is a component of water and most other compounds in the body

Answer 21

Potassium; is important for proper membrane function, nerve impulses and muscle contractions

Answer 22

Sodium is important for nerve impulses and fluid retention

Answer 23

Carbon forms organic compounds

Answer 24

Calcium is found in bones and teeth, important for nerve impulses

Answer 25

Iron is a component of Hemoglobin

Answer 26

If an atom gains or loses one or more electron it is then called an ion.

Answer 27

An ion that gains electrons is called an anion

Answer 28

An ion that loses electrons are called cations

Answer 29

Are a class of important organic molecule that provides energy and structure Sugars are the building blocks for carbohydrates

Answer 30

Lipids are large hydrophobic organic molecules - Chemical messengers - Storage and provision of energy

Answer 31

- made up of amino acids - building tissues and muscles - hormone production; Hormonal proteins such as insulin and oxytocin play a vital role like controlling blood sugar concentration and stimulating contractions during childbirth - provides energy - immune function; antibodies (specialised protein) that provides a specific immune defence against invaders.

Answer 32

- Consist of long chains of nucleotides - are the molecules of the genetic code - are also important as energy carries

Answer 33

Epidermis (including basal cells, melanocytes and keratinocytes) (top layer) Dermis (directly below epidermis) Hypodermis (subcutaneous layer) (just below skin connects the skin to surface muscles)

Answer 34

Outermost layer composed of epithelial cells - Form a protective covering for all of the internal and external surfaces of the body - Avascular, dependent on lower layers for nourishment - keratinised stratified squamous epithelium

Answer 35

Human DNA contains thousands of genes that provide the information essential for heredity

Answer 36

Thoracic cavity

Answer 37

Smooth endoplasmic reticulum

Answer 38

Phospholipids

Answer 39

Smooth muscle cell with contractile proteins

Answer 40

The cell membrane is made up of a phospholipid bilayer. A phospholipid is made up of hydrophilic,water-loving, phosphate head, along with two, hydrophobic, water-hating, lipid (fatty) acid tails. parts and water hating (hydrophobic) lipid part. Phospholipids spontaneously arrange themselves in a double-layered structure with their hydrophobic tails pointing inward and their hydrophilic heads facing outward. Structural features that enable it to perform that feature: lipids 98% -phospholipids :make up the sea of the membrane -cholesterol: essential for membrane structure, embedded between lipid tails, holds the phospholipids together, makes the membrane less fluid -glycolipids: lipids that are attached to a carbohydrate group, only occurs in the outer facing side (ECF) of the mb Proteins 2% -can be integral or peripheral Functions: receptors, enzymes, channel proteins, gated channels, cell identify markers, CAM’s

Answer 41

``` Organ Systems ^ Organs ^ Tissue ^ Cells ^ Chemicals ```

Answer 42

Because a cell membrane is semi-permeable it restricts diffusion of highly charged molecules, such as ions, and large molecules, such as sugars and amino acids The passage of these molecules relies on specific transport proteins embedded in the membrane.

Answer 43

Small hydrophobic molecules and gases like oxygen and carbon dioxide cross membranes rapidly. Small polar molecules, such as water and ethanol, can also pass through membranes, but they do so more slowly. On the other hand, cell membranes restrict diffusion of highly charged molecules, such as ions, and large molecules, such as sugars and amino acids.

Answer 44

``` Skeletal system Muscular system Cardiovascular system Lymphatic system Immune system Respiratory system Digestive system Urinary system Nervous system Integumentary system Endocrine system Reproductive system ```

Answer 45

Major structures: bones, joints and cartilage Major functions: supports and shapes the body. Protects internal organs. Forms some blood cells and stores minerals.

Answer 46

Structures: muscles fascia (sheet of connective tissue) tendons (fibrous collagen attaching muscle to bone) Functions: holds the body erect, makes movement possible. Moves body fluids and generates body heat.

Answer 47

Structures: heart, arteries, veins, capillaries and blood. Functions: blood circulates throughout the body to transport oxygen and nutrients to cells, and to carry waste products to the kidneys where waste is removed by filtration.

Answer 48

Structure: lymph, lymphatic vessels, and lymph nodes Function: removes and transports waste products from the fluid between cells. Destroys harmful substances such as pathogens and cancer cells in the lymph nodes. Returns the filtered lymph to the bloodstream where it becomes plasma again

Answer 49

Structure: Tonsils, spleen, thymus, skin, and specialised blood cells Function: Defends the body against invading pathogens and allergens

Answer 50

Structures: Nose, pharynx, trachea, larynx and lungs Functions: brings oxygen into the body for transportation to the cells. Removes carbon dioxide and some water waste from the body.

Answer 51

Structure: Mouth esophagus, stomach, small intestines, large intestines, liver and pancreas Functions: Digest ingested food so it can be absorbed into the bloodstream. Eliminates solid waste

Answer 52

Structures: kidney, ureters, urinary bladder and urethra Functions: filters blood to remove waste maintains the electrolyte and fluid balance within the body

Answer 53

Structures: nerves, brain and spinal cord Functions: coordinates the reception of stimuli. Transmits messages throughout the body (pns) (cns)

Answer 54

Structures: skin, sebaceous glands, and sweat glands Functions: protects the body against invasion of bacteria. Aids in regulating the body temp and water content.

Answer 55

Structures: adrenal glands, gonads, pancreas, parathyroids, pineal, pituitary, thymus, and thyroid Function: integrates all body functions

Answer 56

Structures: Males: penis and testicles Female: ovaries, uterus, and vagina Function: produces new life

Answer 57

1. Cranial cavity 2. vertebral cavity 3. Pericardial cavity 4. Abdominal cavity 5. Pelvic cavity 6. Pleural cavity 7. Superior mediastinum

Answer 58

Location: Skull Function: Lined by melinges, containing cerebrospinal fluids, to cushion blows and protect brain.

Answer 59

The dorsal cavity is located along the back of the body and head. It contains organs of the nervous system that coordinate body function. Divided into two portions: Cranial cavity -within skull, surrounds and protects the brain Spinal cavity -located within the spinal column, surrounds and protects the spinal cord.

Answer 60

``` DNA carries genetic instructions to tell your cells how to: • Growth • Development • Functioning • Reproduction ```

Answer 61

Deoxyribonucleic acid exists in all living things, even bacteria that isn’t considered living contains DNA. DNA is packaged in the nucleolus The nucleolus is inside the nucleus. The nucleolus contains proteins, nucleic acids and all our DNA. DNA is a long molecule like a twisted ladder called the double helix ladder.

Answer 62

- DNA is long and thin - it gets wrapped around histones - which form nucleosomes and super coils - these are then arranged into chromosomes - chromosomes are housed inside the nucleus.

Answer 63

Human somatic(body) cells have 46(known as diploid number) chromosomes 23 from mum 23 from dad 23 pairs of chromosomes: 22 pairs of homologous autosomes 1 pair of sex chromosomes - females have XX - males have XY Human gametes have 23(haploid) chromosomes

Answer 64

Somatic cells are basically every cell in the body besides the gametes. In humans, a diploid cell has 46 chromosomes. Gametes are sex cells, so the egg and sperm. They are considered haploid because each gamete contains half the number of chromosomes that an organism's somatic cells will have.

Answer 65

- A gene is a small segment of DNA on a chromosome - they provide instructions for A PARTICULAR protein - each chromosome carries thousands and thousands of genes - each gene is always found in the same location of a chromosome.

Answer 66

Genotype= your chromosomes and genes, your unique genetic make up Phenotype= your anatomy and physiology, the expression of your genotypes !WHAT IS EXPRESSED! Phenotypes are determined by your genotype They are also influenced by the environment

Answer 67

Is when same populations may have different versions of gene Different variation of one gene Same corresponding genes on the chromosome found in the locus (plural) I.e BB, Bb,

Answer 68

You inherit two copies of each gene: If they are the same it is called homozygous (eg black hair from mum black B hair from dad B child has black hair BB) If they are different it is called heterozygous (Eg black hair from mum B blonde hair from dad b child will be Bb)

Answer 69

Phenotypes (expression) are determined by your genotype (genetics) For example your black hair is a phenotype resulting from dominant genotypes Genotype= your chromosomes and genes, your unique genetic make up Phenotype= your anatomy and physiology, the expression of your genotypes !WHAT IS EXPRESSED!

Answer 70

Heterozygous of an allele you have two sets of instructions: Dominant/recessive: One allele is dominant and therefore its trait is expressed, the other allele is recessive and so the trait is masked by the dominant allele They can still carry the recessive gene and pass it on to their offspring In order for the recessive trait to be expressed they have to be homozygous Co-dominance: Both alleles are expressed, resulting in a mixture of the two traits, Eg blood type A and B are both dominant If one parent is blood type A and the other is blood type B the offspring will be blood time AB

Answer 71

Autosomal recessive are one of several ways that a trait, disorder, or disease can be passed down through families. An autosomal recessive disorder means two copies of an abnormal gene must be present in order for the disease or trait to develop. Autosomal dominant disorder is similar to autosomal recessive disorders, except the dominant allele is the undesired condition

Answer 72

``` Cells of the Epidermis • Keratinocytes most abundant, produces keratin, arises from the deepest layer of the epidermis • Melanocytes spider-shaped cells, produces melanin, found in the deepest layer of the epidermis . Basal cells ``` ———————- Langerhan’s cells star-shaped macrophage cells, activate immune system, originate from bone marrow • Merkel cells present at the epidermis-dermis junction, associated with nerve endings, function as sensory receptors

Answer 73

Appendages of the Skin • Nails • Glands (oil and sweat) • Hair (and hair follicles)

Answer 74

Nails - What: modifications of the epidermis, densely packed epithelial cells containing fibres of hard keratin (kera = horn) - Where: located distally on the posterior surface of the fingertips and distally on the superior surface of the toes - Why: protection of the underlying nerves aids in picking things up, scratching, digging, grooming, manipulating small objects, etc

Answer 75

Glands - What: clusters of specialised epithelial cells that secrete a substance. eg, oil, sweat, wax, milk, etc - Where: sweat glands: whole body except nipples and parts of external genitalia sebaceous glands: whole body except palms and soles - Why: sweat glands: regulate body temp, remove wastes sebaceous glands: softens skin and hair, ↓bacterial growth, ↓ water loss

Answer 76

Hair - What: shaft: slender filament of keratinised cells root: below the surface, embedded within skin follicle: group of cells that surround the root, holds hair in place - Where: whole body except palms, soles, lips, nipples and parts of the external genitalia - Why: warmth, protection against physical trauma, heat loss, sunlight, detect insects on skin, keep out foreign particles, etc

Answer 77

Functions of the Skin • Protection The skin is the most vulnerable organ of the body. It is constantly exposed to bacteria, abrasions, temperature extremes, chemicals, etc Acts as 3 types of barriers: - Chemical barrier: Skin secretions and melanin - Physical barrier: Continuity of skin, waterproof - Biological barrier: Langerhan’s cells, macrophages

Answer 78

• Body temperature regulation Sweating - 500ml/day at rest (unnoticeable) - up to 12L/day during vigorous exercise • Cutaneous sensation Sensory receptors on the skin allow us to feel light touch, pressure, vibration, tickling (mechanoreceptors), temperature (thermoreceptors), pain (nociceptors), etc Hair follicle receptors – insects, wind, etc • Metabolic function Produces vitamin D (when exposed to UV) for calcium and phosphorous absorption (bone development) • Blood reservoir The dermis is highly vascularised Blood can be temporarily shunted from the skin and relocated to another part of the body that requires it • Excretion and Absorption Removal of nitrogenous wastes such as urea, ammonia, uric acid, and salts, etc in sweat. Absorbs vitamins A, D, E and K and oxygen

Answer 79

Homeostasis refers to the body’s ability to maintain a stable internal environment within a narrow preset range, relative to a variable external environment each bodily structure contributes to keeping internal environment within normal limits, for example the lungs allow just the right amount of oxygen into the body Imbalance and disruption to optimum range for normal body functions • Must be corrected • If not corrected, will result in: - disease (eg, diabetes mellitus, rickets, anaemia, etc) - death

Answer 80

The body has regulating systems: - nervous system (brain, spinal cord and nerves) - endocrine system (glands and hormones) These nerve impulses and/or chemical messengers transmit information needed to maintain homeostasis through Feedback Systems

Answer 81

Feedback System Components Receptor: - receives the “information/stimulus” from the surrounding Control centre-brain - sets the range of values - evaluates the incoming info (thinks about it) - determines next action (decides what to do next) - conveys output to the effector (gives the order) Effector: - receives the order from the control centre - carries out the work = response (ie, brings about the effect)

Answer 82

The response OPPOSES the initial stimuli to REVERSE the change, if one goes down the other goes up. An example of negative feedback is the control of blood sugar (glucose) by insulin. When blood sugar rises, receptors in the body sense a change. In turn, the control centre (pancreas) secretes insulin into the blood to lower blood sugar levels. Once blood sugar levels have reach homeostasis, the pancreas stops releasing insulin.

Answer 83

Positive feedback is a body response that STRENGTHENS or ENHANCES the stimuli to produce an EVEN GREATER (amplified) change. Positive feedback loops are used when you want to produce a large or rapid change. Some examples include: -release of oxytocin (hormone) during childbirth -release of oxytocin during breastfeeding -formation of the platelet plug during blood clotting -activation of immune cells. Childbirth example explained: During labor, a hormone called oxytocin

Answer 84

Oxytocin is produced in the hypothalamus and released by the posterior pituitary It is initiated by physical stimulation such as suckling of the nip In childbirth Increased uterine contractions —> message is sent to the hypothalamus —> hypothalamus produces oxytocin —> oxytocin is then released from the posterior pituitary —> oxytocin secreting neurons travel down to cervix and increase uterine contractions, this positive feedback loop repeats itself with uterine contractions increasing in pressure until the baby is born.

Answer 85

Thermostat in hypothalamus activates cooling mechanisms I I sends message to skin blood vessels to dilate Sends messages to the eccrine gland I I capillaries fill with warm blood Eccrine glands secrete water to skin by evaporation -cooling I heat then radiates from skin surface Eccrine sweat glands extend from out layer of skin to the dermis layer, they are distributed all over the surface layer of the skin, the sweat glands are controlled by sympathetic cholinergic nerves which are controlled by the hypothalamus, the hypothalamus senses core temperature directly, and also has input from temperature receptors in the skin and modified the sweat output. Shivering: When the cor body temperature drops, the shivering reflex is triggered to maintain homeostasis. Skeletal muscles begin to shake in small movements, creating warmth by expending energy.

Answer 86

Thermoregulation. | All thermoregulation mechanisms are designed to return your body to homeostasis. This is a state of equilibrium.

Answer 87

A tiny muscle that attaches to the base of a hair follicle at one end and to the dermal tissue on the other end. In order to generate heat when the body is cold the erector muscles contract all at once, causing the hair to stand up straight on the skin.

Answer 88

Simple diffusion: is the net movement of a (solute) molecule, either in a gas or liquid, from an area of high concentration to an area of low concentration. The rate in which they diffuse is affected by: -mass of molecule -distance -temperature - steepness of gradient Diffusion of chemicals and gases in and out of a cell is an essential activity in human organs. Diffusion of oxygen and carbon dioxide gas occurs in the lungs. Diffusion of water, salts, and waste products occurs in the kidney. Diffusion of calcium from food into cells occurs in the intestines.

Answer 89

A special type of diffusion, referring to the diffusion of water, as opposed to solutes (molecules) along its own concentration gradient. The net movement of water across a selectively permeable mb from a dilute solution to a more concentrated solution as water molecules try to reach equilibrium (balancing of opposing forces)

Answer 90

Facilitated diffusion uses protein carries to transport molecules down a concentration gradient. It is helped along by a protein channel. However, once reached saturation or transport maximum no more molecules will be able to diffuse as you can only transport as many molecules and you can carries. Example:

Answer 91

Active transport requires energy as solutes are pushed against the concentration gradient. It also requires the use of carrier proteins working against the concentration gradient. And example of this are na+/ k- pumps (explain)

Answer 92

Passive transport doesn’t require ATP active transport does. Passive transport moves molecules WITH the concentration gradient (high to low) Active transport moves molecules AGAINST the concentration gradient (low to high)

Answer 93

Allowing certain substances to pass through it but not others. Especially allowing the passage of a solvent but not of certain solutes E.g A semipermeable membrane

Answer 94

Solute - substance (salt) Solvent- liquid (water)

Answer 95

Lipid soluble=

Answer 96

- bacteria (can be good or bad) - fungi/yeast - helminths (can be seen with the naked eye) - viruses (are not considered living) - Protozoa

Answer 97

- very small - not considered living so can not reproduce - must use host machinery to reproduce - can not be cultured (requires a living host) - no cellular structure - no cell wall - protein capsules containing nucleic acid (rna or dna)

Answer 98

- eukaryotic cell - more organised than bacteria - can be uni cellular or multi cellular - cell wall present - capable of reproducing spores

Answer 99

- eukaryotic cell - unicellular - usually motile (can move around)

Answer 100

- eukaryotic cells - mostly unicellular - they have cell walls - capable of independent survival (do not need a host) - can be motile and visible to the naked eye

Answer 101

Bacillus (rod-like) | coccus (spherica)

Answer 102

Prokaryotes are much older than eukaryotes. A prokaryote has no nucleus or membrane bound organelles where as eukaryotes do. A cell wall is not present in a prokaryote and they are mostly unicellular, the cell wall is present in eukaryotes and they are mostly multicellular. A prokaryote are a mass of different things mashed up where as a eukaryote is more complex and developed. Examples of a prokaryote is bacteria, an example of eukaryotes are plants, fungi, animals, yeast, moulds, Protozoa etc.

Answer 103

Only need to know oxygen, Ph and temp Temperature: 10-39 degrees PH: 6-8 Water: Bacteria needs water to reproduce, but can stay dormant in dry conditions Oxygen: aerobic-requires oxygen to survive facultative anaerobic- with or without oxygen Obligate anaerobic-must not have oxygen Nutrients: needed in order to reproduce, chemical requirements: carbon, nitrogen etc. organic growth requirements: vitamins, minerals, amino acids etc Time: needs time to divide/ in ideal conditions (37 deg) can divide every 20 mins. Competition: must be at bay

Answer 104

A gram stain test is very useful in quickly eliminating a big portion of what the bacteria could be. If the bacteria stains blue/ positive it means a thicker cell was is present as it retains the dye If the bacteria stains a pinky red/negative it means it has a thinner cell wall as it has not retained the dye Bacillus will stain blue, coccus will stain red.

Answer 105

Bacteria that normally live in/on the host It lives any where there is surface contact with the outside environment i.e the skin, mouth, GI tract, ears. The skin is mostly G+ cocci, the gut is mostly, G- rods. Normal bacteria lives on our skin and in our gut. It acts as a protective agent for our immune system as different bacteria are constantly fighting for the same space and nutrients, one will usually win and the other will usually die out. Natural flora is already living on us and not causing any harm, however they are there to protect us if more harmful bacteria lands on us.

Answer 106

An opportunistic Pathogen is a pathogen that strikes when your immune system is weak, but not necessarily strong enough to when your immune system is strong. I.e if you’re old you’re more susceptible

Answer 107

- contact transmission - common vehicle transmission - transmission via vectors

Answer 108

-direct (touching source of infection, human to human, kissing, sexual contact, touching open wound) -Indirect (Not human to human, through formites (inanimate objects) -droplet transmission (breathing, sneezing, coughing)

Answer 109

Refers to a source lots of people catch the disease form- it can affect many people at once. Airborne: pathogens carried on air currents for long distances Water-borne: contaminated water carry pathogens which can be transmitted to host bia drinking breathing etc Food-born: food spoilage causing food poisoning.

Answer 110

Vectors are living agents, usually insects that carry the infectious agent from one host to another. Eg mosquitoes, fleas, lice, ticks, bugs. Flies. Mechanical transmission: passive transport of the pathogen on the outside vectors body. Eg fly lands on open wound after landing on faeces matter. Biological transmission: - vector bites a host containing the pathogen - pathogen multiplies in vector - vector bites another host, pathogen is transferred to new host. I.e malaria.

Answer 111

There are two types: Endogenous infection: cause by microbes already in/on the body. E.g thrush Exogenous infection: cause by microbes derived from outside the body Can get in through skin -wounds, cuts, cracks etc. across mucous membranes i.e nose mouth and eyes Portals of exit: Can be the same way they came i.e sneezing, exit the GI tract via the bowel—> can be lead to contaminated water supply. Skin e.g scabs pus, exudates boils, lesions etc.

Answer 112

- pathogens must be present - pathogens must have sufficient virulence - dose acquired must be large enough - portals of entry must be available - host must be susceptible (animals can carry bacteria without being sick)

Answer 113

Adherence: are they good at sticking onto things? Invasiveness (into tissue): maybe it can produce enzymes which can digest or eat into the protective layer and it can burrow its way into the epithelial cell. Evasion: avoid detection/ attack by immune system. Can it mutate? Toxins: does the microbe produce poison? -endotoxins: part of cell wall and released when cell dies -exotoxins: secreted (released) into host tissues by the bacterium. The bacteria doesn’t have to die for then exotoxin to be released.

Answer 114

- skin (physical barrier, no holes, designed to keep things outside) - gastric juices (highly acidic to kill off bacteria) - mucous membranes (sticky, thick, pathogens, viruses dust etc get stuck or swept up and spat out) - urinary flow (the flush motion pushes the bacteria back out) - hair and cilia (traps bacteria or large particles so that they don’t go further into your body) - vaginal secretion (Ph 3.8, 4) - tears, sweat, saliva (contain lycozmes, enzymes that degrade cellular products) - cerumen (ear wax)

Answer 115

A type of cell within the body capable of engulfing and absorbing bacteria and other small cells and particles. They are non-specific, Any invader is attacked the same way. Phago-eat cytosis-cells

Answer 116

The ***lower*** the pH the more ****acidic***the solution, the higher the pH the more ***alkaine/basic*** the solution, **Pure water** has a pH of 7 and is ***neutral***

Answer 117

``` Skin around 5 Blood- 7.35 Vagina- less than 4.5 Stomach- 1-2 Small intestine 6-6.5 Saliva 6-6.5 ```

Answer 118

Natural killer cells are a type of lymphocyte (white blood cell) part of the innate immune system. Made in the bone marrow, once it has matured it comes out and circulates looking for abnormalities and kills it. Kill them off before they turn into a cancer

Answer 119

Is a set of plasma proteins that complement all aspects of the immune response -they promote phagocytosis, inflammation and cell lysis Bunch of plasma proteins/ chemicals that enhance the second line defence

Answer 120

A type of cytokine (chemical) that interferes with viral replication and activates immune cells such as NK, macrophages

Answer 121

It is a localised response to the area of damage. The damaged cells will send chemical messages, the body responds with inflammation This process is supported by phagocytosis

Answer 122

Stage 1: vasodilation - Dead or dying cells release chemical mediators. (Increased vessel diameter, blood flow and permeability of capillaries) - cells and chemicals leave the capillaries and enter the tissues - removal of toxic products and dead cells/debris - explains swelling, redness and heat Stage 2: phagocyte migration - neutrophils are first on site (attracted by chemotaxis, fight hard die young) - then monocytes come (once in the tissue they mature into macrophages or big eaters) - dead phagocytes, damaged tissue, pathogens, debris= pus Stage 3: repair Repair cannot occur until the source of injury (injurious agent) is removed -by mitosis and scar formation -inflammation is essential for healing

Answer 123

To destroy and remove antigens It limits effects of injurious agents It cleans up dead tissue and debris It promotes healing

Answer 124

Its a non-localised or systemic response where the temperature in the hypothalamus resets to attain temp over 37.2 ``` When your body temp rises wbc become more active. Increased metabolism for healing Harder for pathogens to survive Suppress bacterial activity A fever for too long can be detrimental ```

Answer 125

The third line defence is an acquired or specific body defence Aims to kill/destroy pathogen by making antibodies and developing ‘memory’ Its specific The host has to be exposed to the pathogen first The pathogens has surface antigens

Answer 126

Finish answer

Answer 127

Calcitonin slows down the activity of the osteoclasts found in the bone

Answer 128

Produced in the pancreas and it causes the liver to convert stored glycogen into glucose which is released into the blood stream

Answer 129

Produced in the anterior pituitary it stimulates the growth of essentially all tissues of the body including bone

Answer 130

Exocrine glands: Secrete products into ducts which empty into body cavities or body surfaces E.g sweat, oil, mucous, digestive, salivary, mammary Endocrine glands: -secrete products (hormones) directly into bloodstream i.e no ducts E.g hypothalamus, pituitary, thymus, pancreas, thyroid, parathyroid, adrenal, pineal etc

Answer 131

Anterior pituitary communicate via hormones (hypothalamus produces hormones which travel through the blood and Posterior pituitary communicate via neurons

Answer 132

Trophic hormones : are the hormones that work on other glands that tell the gland to release their hormones Inhibitory hormones: tell the gland to stop release that hormone

Answer 133

Growth hormone releasing hormone (GHRH) -trophic Thyroid releasing hormone (TRH) -trophic Thyrotropin-releasing hormone (TRH) -trophic Prolactin releasing hormone (PRH) -trophic Prolactin inhibiting hormone (PIH) -inhibitory Somatostatin/ growth hormone inhibiting hormone (GHIH) -inhibitory It also produces oxytocin and antidiuretic hormone but does not release it, it is stored and released by the posterior pituitary gland

Answer 134

The anterior pituitary gland is under the control of the hypothalamus It produces and secretes: - human growth hormone (hGH) in response to GHRH or GHIH from the hypothalamus - thyroid stimulating hormone (TSH) in response to thyrotropin-releasing hormone (TRH) from hypothalamus - follicle stimulating hormone (FHS)-in response to gonadotrophin from hypothalamus - luteinising hormone (LH) -in response to gonadotrophin from hypothalamus - prolactin (PRL) in response to the PRLRH from hypothalamus - adenocorticotrophic hormone (ACTH) in response to corticotrophin releasing hormone from hypothalamus

Answer 135

Stimulates follicles, affects ovaries and testes, in ovaries causes growth of follicles and estrogen in women and sperm production in men

Answer 136

Regulated by GnRH and feedback systems Affects ovaries and testes: cause ovulation in women, testosterone secretion in men

Answer 137

Regulated by prolactin releasing/ inhibiting hormone Produce milk Affects mammary glands and testes: synthesis of milk in breast feeding women

Answer 138

Regulated by CHR and feedback systems Works on the adrenal glands (on top of your kidneys) Tells your adrenal glands to release its hormones

Answer 139

1. Hypothalamus releases TRH which acts on the ant pit gland 2. Ant pit gland responds by releasing TSH which acts on the thyroid gland 3. Thyroid gland responds by releasing TH into the blood stream 4. The TH acts on target tissues 5. Abundance of TH in the blood feeds back to ant pit gland to stop releasing TSH feeds back to hypothalamus to stop releasing TRH

Answer 140

Does not synthesise hormones, but stores and secretes then when prompted to do so Hormones: -oxytocin (OT) Affects uterus, mammary glands, stimulates smooth muscle contractions eg labour and milk secretion, promotes affection/ bonding -antidiuretic hormone ADH Affects kidneys —> promotes water retention

Answer 141

Located in the throat, anterior to the trachea Responds to TSH (anterior pituitary) to release TH Increases metabolism, oxygen consumption, heat, heart rate Overactive thyroid skinny, gittery, hot Cold all the time, fatigue, fat, etc Important for metabolism Thyroid gland also releases calcitonin: promotes the re-uptake of calcium from the blood to be deposited as bone when blood calcium levels are too high. Calcitonin helps increase calcium absorption in gut, parathyroid hormone does the opposite so that are antagonist

Answer 142

Sits on top of the kidney Responds to ACTH Two parts: cortex and medulla Cortex: (steroids/ the corticoids) - mineralcorticoids - glucocorticoids - androgens Medulla: - epinephrine (adrenaline) - norepinephrine (noradrenaline)

Answer 143

Mineralcorticoids: One of them is aldosterone which causes the reabsorption of sodium, and therefor h2o because it tries to follow the solute Conserves water Glucocorticoids: Cortisol, corticosterone, cortisone —> protein and lipid breakdown, formation of glucose and resistance to stress, anti inflammatory effects Androgens: Stimulates the growth of pubic and axillery hair May contribute to sexdrive Converted to testosterone in males, estrogen in females

Answer 144

Epinephrine Sympathetic NS Norepinephrine Increase in alertness, anxiety, fear, prepares the body for physical activity.

Answer 145

Is both and endocrine and an exocrine gland As an endocrine gland it release glucagon and insulin As an exocrine gland it releases digestive enzymes that help digest your food Glucagon Promotes release of glucose breaks down fats to increase blood glucose, when glucose levels go down glucagon is release to make glucose levels go back up it restore some stored glucose to make levels go back up Insulin : released after you have eaten Absorb glucose and stimulates muscles cells to store glycogen and fat and decrease blood glucose levels These two hormones work together to regulate blood glucose levels making sure its not too high and not too low

Answer 146

-ovaries Estrogen, progesterone, relaxin and inhibin Regulates reproductive cycle maintain pregnancy and prepare mammary glands for lactation Testes Testosterone and inhibin Masculinising hormones, regulating spermatogenesis and development of male secondary sex characteristics

Answer 147

The nervous system is fast, there are dedicated neural pathways, which induce a fast electrochemical response The hormonal system has no dedicated pathways, chemicals are released into the blood stream, effects are widespread and sustained, response is relatively slow

Answer 148

Steroid hormones - derived from cholesterol (lipids) - includes sex steroids (estrogens, progesterone, testosterone) corticosteroids-from adrenal cortex, calctriol etc Peptide hormones - derived from amino acids (proteins/polypeptides) - including post pit hormones, hypothalamic hormones, pancreatic hormones, most ant pit hormones etc Monoamines - derived from amino acids retaining an amino group - includes neurotransmitters such as epinephrine, norepinephrine, dopamine, melatonin and thyroid hormone

Answer 149

Hormones travel in the blood, blood is mostly water Peptide hormones and most monamines are hydrophilic and therefore travel freely in the blood I.e they travel unbound to a transport protein Steroid hormones and thyroid hormones are hydrophilic and cannot travel freely in the blood therefore steroid hormones are bound to protein carries so that they can travel freely around the blood

Answer 150

Transport proteins are albumins and globulins- made by liver (these act as little carries) Only unbound/ free hormones are allowed to exit the capillaries and reach target cells Bound hormones remain inactive and circulate in the blood -they will not be broken down by enzymes -prevents excretion by kidneys -acts as a long-lasting blood reservoir (Eg TH) for example you wont find the effects of removing thyroid gland for several weeks after because the thyroid has produced enough TH to circulate in blood attached to protein, finally when that is used up is when its absence will become evident. Long lasting Where as unbound hormones only last minutes

Answer 151

Hormones can only act on cells that have receptors for them (target cells) Hormone receptors are specific When hormone binds to a receptor, it acts as a switch to turn metabolic pathways on or off Receptors are located: On cell surface (plasma membrane) Intracellular (the membranes of mitochondria, nucleus and other organelles)

Answer 152

Each target cell will have thousands of receptors for a particular hormone Saturation: is when all the receptors on the target cell are already bound to a hormone molecule, adding more hormone will not increase the effect Target cells may respond to many different hormones and therefore possess many different types of receptors

Answer 153

Generally, hormones bind to receptors and: - initiate synthesis of new molecules -direct the production of - alters membrane permeability -make more or less - alters the rate of metabolism Each target hormone cell responds to a hormone differently e.g liver cells, insulin reticulate glycogenesis, at adipocyte, insulin stimulates lipogenesis

Answer 154

-hydrophobic lipid-soluble hormones have no problems diffusing through the plasma membrane into the cytoplasm because the membrane is also made of lipid —> bind to the receptor inside the cell —> activate receptors (turn certain genes on/off) —> new mRNA is formed —> synthesis of new protein/ molecule —> new protein alter cellular activity (metabolism)

Answer 155

-hydrophobic water-soluble hormones are unable to enter the cell —>hormones bind to cell surface receptor (acts as first messenger) —> once bound, a second messenger pt (cAMP) is generated inside the cell —> second messenger takes the message into the cell and causes the desired response through a series of cascading events —> then quickly broke down by enzymes and message is stopped

Answer 156

Support; structural support Storage; of minerals, lipids, and other important ions Blood cell production; red/white blood cells Protection; of soft tissue Leverage; acts as levers for muscles Acid-base balance; absorbing or releasing alkaline salts (blood has to be around 7.35-7.45

Answer 157

Bones -skeleton structure Tendons -attach muscle to bone Ligaments -attach bone to bone

Answer 158

Red bone marrow in adults is found at the ends of the long bones i.e head of humorous or flat bones It produces blood cells Yellow bone marrow is everywhere else For storage of minerals and lipids (can convert back to red bone marrow)

Answer 159

Compact bone: - strongest form - structure and support - heavy makes up bulk of bones - resists stress - osteons (compact columns) Spongy bone: - Distributes stress - trabeculae (crisscross beams) - storage of marrow - interior of bone - lightweight

Answer 160

Periosteum - Thick vascular fibrous membrane surrounding bone - attachment s

Answer 161

``` Periosteum – Thick vascular fibrous membrane surrounding bone – Attachment site for tendons and ligaments – Contains osteoprogenitor cells • Endosteum – Thin vascular membrane lining the medullary cavity – Contains osteoprogenitor cells ```

Answer 162

Osteoprogenitor cells - stem cells that give rise to osteoblasts - assists in small repairs Osteoblasts (found in periosteum) - immature bone cells that deposit minerals to form bone Osteocytes - matured osteoblasts trapped within a lacuna - responsible for maintaining the surrounding matrix by continually dissolving and depositing new matrix Osteoclasts (derived from bone marrow related to white blood cells) - not related to osteoprogenitor cells - large, multinucleated cells that dissolve bone matrix

Answer 163

Made up glial cells it is a protective covering The portion of the nerve divers that are myelinated are known as white matter The portion of the nerve fibers that are unmyelinated are known as grey matter

Answer 164

Osteoprogenitor cells - stem cells that give rise to osteoblasts - assists in small repairs Osteoblasts - immature bone cells that deposit minerals to form bone Osteocytes - matured osteoblasts trapped within a lacuna - responsible for maintaining the surrounding matrix by continually dissolving and depositing new matrix Osteoclasts - not related to osteoprogenitor cells - large, multinucleated cells that dissolve bone matrix

Answer 165

Epiphysis, metaphysis, diaphysis, epiphysis

Answer 166

Bone Matrix Bone belongs to which tissue type? Bone matrix is made up of: Minerals (inorganic) - roughly two thirds - mainly calcium phosphates, calcium hydroxyapatite - resists compression, responsible for ‘hardness’, can shatter if twisted Proteins - roughly one third - mainly collagen, proteoglycans, cytokines, growth factors - resists tension, responsible for ‘flexibility’, allows some twisting

Answer 167

The Axial Skeleton Skull – 8 cranial bones – 14 facial bones Vertebral column – 24 vertebrae – Sacrum – Coccyx Thoracic cage – 24 ribs – sternum

Answer 168

A joint/articulation occurs where two or more bones meet (regardless of movement) There are four structural classes of joints: - Bony (synostosis) - Fibrous (synarthrosis) - Cartilaginous (amphiarthrosis) - Synovial (diarthrosis)

Answer 169

Bony Joints • Are also known as synostosis joints • An immovable joint formed when the gap between two bones ossify, making it a single bone • Bony joints can start off being fibrous or cartilaginous joints which later ossify Eg the epiphysis and diaphysis in long bones are initially joined by cartilaginous joints (during childhood and adolescence) which later become a synostosis

Answer 170

Are also known as synarthrosis joints • Occurs where two adjacent bones (ie, bones that are next to each other) are bound together by collagen fibres • There are 3 functional types of fibrous joints: - Sutures. +collagen fibres are short and joint is relatively immovable - Gomphoses - Syndesmoses collagen fibres are longer, attached bones are more movable

Answer 171

``` Are also known as amphiarthrosis joints • Occurs where two bones are linked together by cartilage • There are 2 functional types of cartilaginous joints: - Synchondroses - Symphyses Synchondrosis - two bones are attached by hyaline cartilage eg, between diaphysis and epiphysis of long bones eg, between first rib and sternum • Symphysis - two bones are attached by fibrocartilage eg, pubic symphysis and vertebrae ``` ``` Cartilage: Hyaline – Most common in body – Abundant in type II collagen (strength) – Precursor of bone – Located in ribs, nose, larynx, trachea • Fibro – Strongest – Dense collagen fibres – Located in intervertebral discs, joint capsule, ligaments • Elastic – Elastic fibres – Located in external ear, epiglottis, larynx ```

Answer 172

The most freely movable joints in the body • Most of the joints in the body are synovial joints • Two adjacent bones are separated by a fibrous joint capsule, lined by synovial membrane and filled with synovial fluid (joint cavity) • Synovial fluid is a slippery, viscous fluid which is secreted by the synovial membrane for: - lubrication of the joint - nourishment and waste removal • The articulating surfaces of the two bones are covered by hyaline cartilage for protection of bone, weight dissipation and shock absorption

Answer 173

Fibro: protects bones from rubbing together, it doesn’t allow a lot of movement, pads knees, between pubic bones of pelvis intervertebral discs FINISH

Answer 174

A cell placed in a hypotonic solution will experience net flow of water into the cell A cell placed in a hypertonic solution will experience net flow of water out of the cell A cell placed in a isotonic solution will experience no net flow of water (the cell would remain the same volume)

Answer 175

A process where a single cell divides twice to produce four cells containing half the original number of genetic information

Answer 176

A type of cell division that results in two daughter cells Mieosis ( four daughter cells)

Answer 177

If a cell is no longer needed they commit suicide by activating intracellular death program

Answer 178

Sensory receptors all over the body and are known as acute or new pain

Answer 179

Located in the dermis, skeletal muscles, liver and hypothalamus signal warmth and cooling respectively in our skin

Answer 180

Extension: increases in an angle as in straightening a joint Flexion: decreases an angle, as in bending a joint Rotation: turns a bone on its own axis Adbuction: moves away from the midline Adduction: moves towards the midline

Answer 181

A one way direction only, through vasculature (blood vessels) Both the left and right side will pump into blood vessels

Answer 182

The CNS ( which makes decisions and generates motor messages) : - brain; little bit of grey matter outside (cell bodies) lots of white matter inside (myelinated axons) - spinal cord; lots of white matter on the outside (myelinated axons) little bit of grey matter on the inside (cell bodies) The PNS: All the nerves outside the CNS that connect the CNS to the organs, limbs, skin etc.

Answer 183

Somatic: -Skeletal (controlled/ voluntary) Autonomic: -cardiac, smooth muscle, glands (uncontrolled/ involuntary) —> autonomic is then divided into: sympathetic and parasympathetic If messages are going via my sympathetic muscles to my cardiac muscles it will speed it up.

Answer 184

- If the first and second line defence are breached the third line of defence aims to kill/ destroy pathogen by making antibodies and developing memory. - It is specific immunity - The host is exposed to the pathogen (disease cause) - Pathogens have surface antigens - B and T lymphocytes are capable of recognising these antigens as ‘foreign’ and mount an attack

Answer 185

1. Phagocytic APCs engulf the extracellular pathogens 2. Lysosomal action produces antigenic fragments 3. The endoplasmic reticulum produces class II MHC proteins. 4. Antigenic fragments are bound to class II MHC proteins 5. Antigenic fragments are displayed by class II MHC proteins on the plasma membrane 6. B and T lymphocytes are capable of recognising these antigens as ‘foreign’ and mount an attack

Answer 186

First line: Is non-specific and aims to prevent pathogen from entering the body through protective mechanism such as skin, mucous membranes, hair and cilia, gastric juices, tears, sweat, saliva etc. Second line: Is non-specific and aims to kill/ destroy pathogens that breech the first line defence before any harm is done. ANY invader inside is attacked the same way which involves leukocytes (white blood cells)

Answer 187

So it can reach and nourish all tissues of the body. | -valves and gravity allow us to travel in the one direction

Answer 188

The persons right and the persons left

Answer 189

The left side is oxygenated and the right side is deoxygenated

Answer 190

Medial from the lungs Superior to the diaphragm Deep to the sternum The heart belongs to the thoracic cavity, in the middle but slightly pointed to the left The apex lies on the diaphragm on the bottom left, and the base of the heart is the opposite top region of the heart The heart is enclosed in a bag called the pericardium to protect it

Answer 191

``` The pericardium is a bag that the heart sits in, It anchors the heart inside the cavity. And protects it from: Over stretching From rubbing on other organs and from friction; pain, wear and tear ``` It is comprised of two layers - Fibrous and serous It has cavity containing pericardial fluid It surrounds and stabilises the heart

Answer 192

3 layers of heart of the heart wall then the sac that surrounds it. -epicardium-connective tissue Anchors(the heart to the cavity), support -myocardium (the middle layer)-muscle; contraction Moves/pushes blood through the heart -Endocardium (inner most layer)-epithelial (you will find this layer covering chambers and covering valves) -secretes, absorbs, protects —>allows for waste to go either way

Answer 193

The left ventricle has more muscles tissue as it has to pump out to the whole body The right side will pump blood that goes to the lungs, it doesn’t need to travel as far so it doesn’t require as much muscle tissue

Answer 194

The difference in volume and pressure with in the chambers is what is going to make blood flow Blood will also want to go from a high pressure to a low pressure, down its concentrated gradient Volume: the size of the chamber Pressure: number of times a molecule collides with the wall of a chamber/vessel More molecules= higher pressure Increase in volume = Decrease in pressure Decrease in volume = Increase in pressure Blood flows from veins to atria to ventricles to arteries due to volume and pressure changes

Answer 195

Valves open and close passively (not directed by nerves) Through blood pushing against them The turbulence of blood opens and shuts them

Answer 196

- tricuspid | - bicuspid (mitral)

Answer 197

- Between your right ventricle and your pulmonary trunk you have your pulmonary valves - Between your left ventricle and your aorta you have your aortic valves So your semilunar valves prevent your blood from flowing back from your arteries into you ventricles

Answer 198

The chordae tendineae are not tendons, but they resemble tendons. They are fibrous tissue which hold the valve to the muscle. We need the chordae tendineae to stop the valve from flinging into the atrium under high pressure.

Answer 199

Vena cava - superior vena cava: which carries blood into the right atrium from above the heart - Inferior vena cava: which carries blood into the right atrium from below the heart Pulmonary vessels - pulmonary arteries - pulmonary veins Aorta -distributes oxygenated blood to all parts of the body

Answer 200

The pulmonary veins | -then into the left ventricle and up through the aorta

Answer 201

The one that takes blood from the heart to the tissue back to the heart. The systemic starts at the left ventricle, through the aorta down through the body and back up into the right atrium.

Answer 202

Pulmonary route takes the blood from the heart to the lungs and back to the heart The pulmonary starts from the right ventricle, up through the trunks to the lungs and then back through into the left atrium.

Answer 203

The hepatic portal vein is the only vein that goes from organ to organ, rather than organ to heart. For example, from digestive organs i.e small intestine to the liver. All other veins go from organ to heart. It goes organ to organ to deliver nutrients straight from the GI tract to the liver where they are stored.

Answer 204

The heart does not take blood for nourishment from its own chambers, the heart has its own blood vessels, the coronary circulation is the blood vessels that supply the heart with oxygen and nutrients. Clinical notes: people can develop heart disease if the coronary arteries become blocked

Answer 205

Groups of cells that initiate nerve impulses (i.e depolarisation, re polarisation) The conduction system ensures that every part of your heart receives a message so that it can contract.

Answer 206

The SA node is a collection of nerve like cells that sets the heart rate and rhythm. It sits in the wall of the right atrium The SA node supplies the Atria(both left and right) with messages to contract, but not the ventricle. The SA node sets your heart rate high and your parasympathetic nervous system is constantly stimulating the SA node to bring down the heart rate.

Answer 207

The AV node sits between the atria and the ventricles. The message travels from the SA node to the AV node, to tell the ventricles its now their time to contract

Answer 208

It sits in the septum and carries impulses to left and right bundle branches

Answer 209

Are fibres that distribute impulses through ventricles

Answer 210

An ECG is a machine that records and measures electrical activity that accompanies each heart beat These electrical signals are recorded on graph Information about functioning of the heart Especially useful if damaged

Answer 211

Depolarisation: stimulates action | Re polarisation: stimulates relaxation

Answer 212

There is, it is hidden by the QRS.

Answer 213

Artial systole (contraction) Artial diastole (relaxation) Ventricular systole Ventricular diastole

Answer 214

Heart (meaning all four chambers) are relaxed -diastole Gravity pushes blood into the atria Pressure in the atrium is greater than pressure in the ventricles AV valves are open Blood flows down (70 percent during rest)

Answer 215

No, | Because then you would get a back flow of blood

Answer 216

Electrical signal from SA node —> atrial depolarisation Atrial contraction Squeezes last 30 percent of blood in the ventricles Once the blood has gone from the atria to the ventricles, the atria can relax again = atrial diastole = (repolarisation)

Answer 217

Electrical signal from AV node —>ventricular depolarisation Ventricles contract and build pressure When the ventricle pressure is higher than the atrium the AV valve snaps shut, preventing backflow (first heart sound, “lubb”) Ventricle keeps contracting, decreases volume Rapid pressure increase When the ventricle pressure is greater than the artery the SL valve forced open and blood rushes into artery The ventricle is empty, the muscle relaxes Ventricular diastole (repolarisation)

Answer 218

Arteries Pulmonary, aorta - carry blood away from the heart - they are elastic (larger ones that stretches and recoils) and muscular (medium size artery such as coronary, renal, biracial) Arterioles Feed into and supply the tissue. These are the smallest branches of arteries. Mainly smooth muscle Capillaries - with in the tissue the arterioles feed into lots and lots of capillaries - smallest blood vessels, small in diametre and thin walls which allow for chemical and gasses diffusion across walls - location of exchange between blood and interstitial fluid **you can not make exchanges anywhere else other than your capillaries** Capillaries have epithelial tissue which allow for this exchange to occur, with a little bit of connective tissue to provide structural integrity and support. Venues -smallest of the veins, collect blood from the capillaries which has anything in excess or anything in waste They then combine to form large (vena cava) and medium sized veins which return blood to the heart.

Answer 219

They attach to the heart Vein: superior and inferior venae cavae carrying deoxygenated blood Pulmonary arteries and veins: pulmonary arteries: deoxygenated, veins: oxygenated, aorta: oxygenated

Answer 220

The three layers surrounding the lumen are: - tunica intima: epithelial (intima-te contact with blood) if its made up of epithelial tissue its going to serve to protect it, or exchange, absorption, secretion - tunica media: muscle (the layer that’s going to allow for the blood vessels to contract) -vasoconstriction- the muscle part in the media that is allowing for that - tunica externa: connective, provides support, don’t want blood vessels to burst to provides strength and anchoring. * **depending on the size of the vessel they may loose layers*** * ** depending on which vessel it is, it will vary in amount of layer***

Answer 221

The answer is always the sympathetic nervous system. How does it do both? Depends on which receptor neurotransmitters bind to as to what it does.

Answer 222

Because it has a thicker muscle layer

Answer 223

Veins; connective tissue Arteries; muscle Structure determines function If a vessel has more connective tissue and very little smooth muscle, it could be considered a passive path Arteries are active because they have muscle, muscles pump, muscles need energy.

Answer 224

Arterioles are made of smooth muscle and can therefore relax or contract according to how the blood needs to be delegated throughout the body

Answer 225

They are very small with thin walls therefore mainly made up on epithelium tissue, so that they can exchange nutrients and waste between blood and tissue. Blood flow is very slow through the capillaries, but that is a good as it allows time for adequate exchange

Answer 226

Because the pressure is much lower Because they have bigger lumens, thinner walls, walls are mainly connective tissue and low pressure. Sympathetic nervous system can cause them to constrict then we need. Veins are a good blood resvoir Low pressure because so far away from left ventricle which imparts pressure to blood.

Answer 227

Valve opens above contracting muscle, valve closes below contracting muscle Veins have valves because blood is a-posing gravity. Skeletal muscle, respiratory pump, valve.

Answer 228

Its the volume of blood flowing through you vessel within a particular unit of time, in order for blood to flow there needs to be a pressure difference, blood is always going to flow from a higher pressure to a lower. For example from your aorta to your capillaries. The vessel length, ***vessel diameter***, viscosity of blood. Bumping against the wall is resistance. Blood flow decreases as resistance increases.

Answer 229

Pressure: blood always flows from a higher to a lower pressure Resistance: as blood is flowing it always encounters resistance, what is the greatest determinant of resistance? Vessel diameter Velocity: if i make my diameter smaller the speed of blood flow is going to be slower. |

Answer 230

Hydrostatic pressure is pressure of fluid against the wall of a vessel . At the arteriole end it is the larger hydrostatic pressure which is going to push fluid and solutes into our tissues. Oncotic pressure is due to plasma proteins At the venule end it is the larger osmotic pressure because we want to bring waste and fluid back into our veins. Osmotic pressure reabsorbs water solutes back into the capillaries Any excess interstitial fluid drains into the lymphatic system. Oncotic and osmotic are used interchangeably It is this osmotic pressure created by proteins which will pull that fluid and waste back into the capillary

Answer 231

It is the amount of blood which is pumped by each ventricle every minute. The same thing always happens on both sides of the heart. The ventricles eject blood which each heart beat that is the STROKE volume. How is this different to the cardiac output? The cardiac output is not every beat, but PER MINUTE So how much am i ejecting per minute?

Answer 232

The beats per minute (HR) And Stroke volume/ blood per beat (SV)

Answer 233

The end diastolic volume EDV is a determinant of stroke volume It refers to how much blood is in the ventricle when it is ready to start contracting and therefore how much can i pump into my artery. Stroke volume is the amount at the start (EDV)- amount left behind (ESV)

Answer 234

How much blood the ventricle can eject I.e can i pump out 100 percent or only 50 percent, we want to pump out as much as much as we take in A healthy heart will pump out as much as it takes in

Answer 235

CO = SV x HR 70ml/beat 75bpm 70x75=5250ml

Answer 236

By altering the stroke volume or heart rate depending on the changing oxygen needs etc.

Answer 237

The difference between resting output and maximum possible

Answer 238

Preload: how much can my ventricle stretch? The heart has elastic fibres which allow for it to stretch to a degree, however it is restricted by its the pericardium. If i want to increase stroke volume and therefore increase cardiac output, ventricle stretches more to accomodate more blood. Like a rubber band Therefore : preload: Is the stretch in muscle fibres The more stretch in a muscle the more strongly it can contract Therefore more blood during diastole=stronger contraction After load: Pressure ventricle needs to reach to force open SL valve and eject blood They need to overcome the pressure in the arteries. The higher the pressure in the arteries, the more blood remains in your ventricle which is the END SYSTOLIC VOLUME

Answer 239

Contractility relates to preload. It is the strength of contraction Where i have an increase in stretch and an increase in blood volume there needs to be a forceful contraction to eject the blood Both autonomic innervation and hormones will help this forceful contraction Autonomic innervation - sympathetic (sympathetic releases noradrenaline as a neurotransmitter which is going to bind to receptors to cause more calcium to be released) - parasympathetic Hormones -adrenaline/noradrenaline I.e calcium (the more calcium i have i am allowing more and more myosin to bind to actin which allows for more muscle contraction) Noradrenaline as a neurotransmitter will cause the adrenal cortex to release adrenaline and noradrenaline as hormones and you get a more enhanced effect.

Answer 240

We need to stretch more We need to contract more forcefully We need to overcome the pressure in the arteries

Answer 241

Regulation of heart rate: SA node- pacemaker, sets the rate (generally sets it to 90-100 beats per minute) Parasympathetic will bring it down to about 60 Therefore body is always modify according to need i.e oxygen need, blood volume This is essential for rapid response. Vegas nerve**** only one to remember

Answer 242

Medulla oblongata: controls cardiovascular, respiratory -controls sympathetic and parasympathetic neurones Sympathetic - increases HR Motor fibres releases noradrenaline If my heart rate was low the medulla would send messages via my sympathetic motor fibres to the SA node. And say quick! Start depolarising more! We need to get this heart rate going Viceversa with parasympathetic Parasympathetic -decreases HR Motor fibres release ACH

Answer 243

Chemical regulation: Hormones: -adrenaline/ noradrenaline Work with the neurotransmitters to increase my response, makes heart beat faster -increase HR

Answer 244

At rest: The EDV is low The myocardium stretches less The stroke volume is low At work: Increase in Venus return (skeletal muscles working hard so there is an increase in blood returning to the right side of heart) —> because veins can hold large amounts of blood in lumen. During exercise the sympathetic causes the veins to contract which shoots blood back up to right side. Increase in heart stretch Increase in force of contraction (more calcium released into muscle cells due to sympathetic nervous system) Increase in stroke volume Therefore more oxygen to tissues SNS also stimulates SA node Increase in stroke volume and increase in heart rate will affect CO (cardiac output)

Answer 245

When the ventricle contracts it pushes blood out to the artery which bangs against the wall which is your systolic pressure (Peak arterial pressure during ventricular systole/contraction) Diastolic pressure: Minimum arterial pressure during diastole/ relaxation

Answer 246

The difference between systolic pressure and diastolic pressure

Answer 247

MAP = diastolic pressure + 1/3 pulse pressure

Answer 248

-cardiac output (Volume of blood pumped by the heart) ->stroke volume, heart rate Total peripheral resistance - resistance of entire cardiovascular system - diameter of arterioles * vasoconstriction =increase resistance * vasodilation= decrease in resistance

Answer 249

A reflex that aims to restore blood pressure to what is has to be. - blood pressure homeostasis * negative feedback Only monitors minute to minute changes in blood pressure short term regulation of blood pressure - baroreceptors * carotid sinuses and aortic sinuses These receptors will detect stretch, afferent nerve fires more action potentials to the medulla to signal what there is a change in pressure levels that need to be fixed In order to change the blood pressure need to change cardiac output (heart rate and stroke volume) and total peripheral resistance Parasympathetic will slow down the heart rate and stroke volume and thus decrease the blood pressure

Answer 250

Yes it is a connective tissue. Because it has cells surrounded by a liquid matrix. -there are red and white blood cells and platelets in blood. Why do males have more blood than females? Because they have more muscle. Blood is also made up of water

Answer 251

7.35-7.45 (alkaline) Vicious- 5x thick water- because there are a lot of proteins in the blood which give it that thicker consistency ** hydrogen makes something more acidic**

Answer 252

Plasma -water and proteins Which carries nutrients, hormones, gases, wastes and electrolytes Cells 45 percent of blood Include red blood cells, white blood cells, platelets All formed in the bone marrow (stem cell) -one stem cell will produce all three of these cells, based on the message its receives from some sort of chemical.

Answer 253

To transport Oxygen to our cells, nutrients (i.e glucose, amino acids, fatty acids) to our cells, waste (which either goes to our lungs Co2 or to the kidneys), hormones, drugs (bind to the receptors on our cells) Regulation Body temperature, pH, fluid volume The blood vessels supplying the skin with vasodilate, more heat is then lost to the surface. pH= more hydrogen ions you have in the blood the more acidic it will be Fluid volume= osmotic pressure generated by your proteins and draw fluid back it Protection Blood loss, infection How do we protect from blood loss? Platelets White blood cells help us from infection

Answer 254

Erythrocytes Transport oxygen -haemoglobin- component of your red blood cell, that carries oxygen. red (iron) Someone who suffers from insufficient haemoglobin levels is anaemic (doesn’t have enough oxygen going around the body) No nucleus ``` Biconcave disks (donut shaped) RBC are donut shaped and flexible Large surface area, flexible in shape ``` Its important that they are flexible to adjust to the diameter of the vessel they travel through. I.e will need to fit through both an artery and arterioles and capillaries. Only the oxygen that can diffuse into from the blood and into the tissues.

Answer 255

If it is carrying four oxygen molecules A haemoglobin molecule will have 4 chains, 4 haem groups, four irons attached to the haems Haemoglobin is at captaincy if it is carrying four oxygen molecules.

Answer 256

They relate to immunity, they helps us to fight any foreign microbes Neutrophils- nonspecific Lymphocytes - specific (T and B cells) T-attacks B cells produce antibodies Monocytes - when they enter into your tissue they become macrophages Eosinophils -target parocyotes Basophils - release histomene to give you that inflammatory response Never let monkeys eat bananas = WBC

Answer 257

Needed for the clotting process -fragments of very big cells (Megakaryocytes) -essential for clotting (haemostasis) so that we don’t bleed

Answer 258

Every cell in your body has an antigen which is basically a marker that identify the cell as being yours An antigen= a protein marker that identifies that cell as yours. - cell surface proteins that identify cells to immune system - normal cells are ignored and foreign cells attacked Antigen-maker on the cell.

Answer 259

* *Antibodies travel in BLOOD** * *you will always have the opposite antibody to the antigen** ``` A (surface antigen A) -Type B antibodies B (surface antigen B) -Type A antibodies AB (surface antigen AB) -Neither A nor B antibodies O (neither A or B) Both A and B antibodies ``` Positive is D antigen

Answer 260

It means to stop bleeding 3 steps: 3 stages to stop bleeding 1) vascular spasm Damage to smooth muscle causes immediate vasoconstriction to limit the amount of blood lost 2) platelet plug formation Exposed collagen lets platelets stick to them, they release chemicals (chemotactic substances) which attract more platelets to the area **thromboxane Az*** 3) coagulation (clotting) Turn blood from a liquid to a gel (Final step clot retraction; platelets pull on fibrin-threads contract, pulls vessels walls closer together. Permits healing) (then plasmin breaks fibrin down, this is called fibrinolysis) There are two pathways Intrinsic -damage to blood vessel collagen exposed Longer pathway, slower pathway more steps involved takes longer to clot blood in that vessel Extrinsic -damage to a tissue, works on blood that’s escaped to a tissue A lot quicker to begin and a lot shorter, clotted immediately But they both aim to do the same thing which is clot blood, common pathway. Prothrombin activator—> prothrombin —>thrombin (essential for the blood clotting process)

Answer 261

Prothrombin activator —> prothrombin (protein) —>thrombin (enzyme) —>fibrinogen —>fibrin

Answer 262

Cellular respiration Oxygen + glucose (food) + water +carbon dioxide +heart + ATP The resp system works with the cardiovascular system to deliver O2 from the lungs to the tissue cells and to remove the co2 from tissue cells and deliver to the lungs Failure of either of these systems is going to result in not enough oxygen going into the tissue Ischema-not enough blood

Answer 263

Provide extensive surface area for gas exchange between air and circulating blood Move air to and from exchange surfaces of lungs Protect respiratory surfaces from dehydration, temperature changes and pathogens

Answer 264

Produce sound; such as speech, laughing, crying, signing Sense of smell Control of blood pH (excess co2–>acidosis(too lower acid in the blood)) Breathing creates pressure gradient, aids in lymphatic and venous return Valsalva manoeuvre: breath hold used in urination, defecation and childbirth.

Answer 265

Conducting zone: Structure that don’t participate in gas exchange but provide rigid passageways that allow air to reach the alveoli Respiratory zone: The structure that actually participates in gas exchange Including: respiratory bronchiole, alveolar duct, alveolar sacs and alveoli Alveoli are air-filled pockets within the lungs where all gas exchange takes place

Answer 266

Airways—> for conduction Lungs —> for gas exchange Respiratory muscles—> for ventilation

Answer 267

Nose and nasal cavity: Extends from nostrils to the choanae. Nasal cavity contains folds of tissue- superior, middle and inferior choncae. Covered in ciliated mucous membranes and hair The nose is the primary passage way for air entering the respiratory system, the narrow passage way ensures of inspired air comes in contact with mucous membranes —> warms air, moistens the air, cleans the air Removes dust and bacteria Villa sweep debris towards the pharynx to be swallowed and digested If you breath with your mouth its dry its not moisten its not clean

Answer 268

The throat. It is divided into 3 divisions: Nasopharynx Oropharynx Laryngopharynx L-shaped cavity that houses the tonsils The function of the pharynx; inspired air is forced to make a 90 degrees turn, larger particles are trapped on the posterior wall of the nasopharynx mucous

Answer 269

The voice box Cartilaginous chamber Keeps food and drink out of trachea. Glottis, epiglottis and laryngeal muscles block off trachea opening during swallowing.

Answer 270

The pipe air travels through Anterior to the esophagus (food and liquid) Internal lining is ciliated mucosa Branches off into the two primary bronchi (one into the left lung one into the right lung) Function: Globet cells secrete mucous to trap particles. Ciliated cells beat in a wave- like manner to propel mucous UP to the back of the throat where you can swallow or spit it out. Held open by cartilage rings Esophagus is collapsed until food is consumed.

Answer 271

Bronchi and trachea and nasal cavity contain receptors which are sensitive to foreigne/irritating matter When stimulated, message is sent to medulla oblongata (brain) and cough/ .sneeze reflex is initiated. Abdominal muscles contract-pressure in lung increases-glottis opens suddenly- air rushes out-foreign particles expelled.

Answer 272

The bronchial tree includes the trachea (trunk) and the two primary bronchi (left and right, connected into the lungs) The secondary bronchi contains progressively less cartilage and more smooth muscle Respiratory bronchioles mark the beginning of the respiratory zone-presence of alveoli (only at the alveoli does gas exchange occur)

Answer 273

Bronchodialtion: caused by sympathetic activation (sympathetic is preparing you for flight or fight—>more air needed) (more oxygen more cellular respiration more ATP more cellular work) Enlarges luminal diameter of airway Reduces airway resistance —> increased airflow Bronchoconstriction: Reduces Luminal diameter or airway Increases airway resistance—> decreased airflow Caused by: parasympathetic activation, histamine release (allergic reaction) Clinical importance - asthma

Answer 274

Aveolar sacs: grape like clusters of alveoli Alveoli: tiny air sacs composed of a single squamous cell (type 1 alveolar cells) Very thin for diffusion of gases Alveoli are dead ends for micro organism- macrophages inside the ale doll engulf microbes/debris and gent swept towards pharynx to be swallowed Air from alveoli into blood Co2 from blood into alveoli Important: alveoli have a huge surface area and are very thing (1 simple squamous cell) to allow for rapid gas exchange, they are surrounded by capillaries so that gas exchange can occur with the blood

Answer 275

Oily secretion made by the type 2 alveolar cells Contains phospholipids and proteins Coats alveolar surface and reduces surface tension -easier to inflate alveoli -prevent alveoli collapsing at end-expiration

Answer 276

Type 1: are the cells that make up the alveoli | Type 2: are the cells that make the surfactant

Answer 277

Nose/mouth Breath with your nose, because it cleans the air, moistens the air and warms the air. —>pharynx Throat —>trachea —>bronchi —>bronchioles —> alveoli

Answer 278

X2 Housed in the thoracic cavity Protected by the thoracic cage (ribs, sternum, vertebrae) Sit on top of the diaphragm The left lung is a little bit smaller than the right lung as it has to make way for the heart.

Answer 279

The lung is enclosed in a cavity lined by 2 membranes: The lining of the inside of your rib cage is called the parietal pleura The lining on the surface of the lung is called the visceral pleura In between those linings is the pleura cavity which is filled with fluid; the fluid is there to lubricate when the lungs expand and deflate Also creates vacuum between rib cage and lungs keeping them connected.

Answer 280

Movement of air into and out of the lungs Inspiration/inhalation/ breathing in Expiration/ exhalation/ breathing out Occurs between the upper respiratory tract and the lower respiratory tract

Answer 281

In order for ventilation to occur, a pressure gradient between the external atmosphere and the internal lungs must exist. We cannot control atmospheric pressure (760mmHg) so we need to decrease our lung pressure so that it falls below the atmospheric pressure to create a gradient.

Answer 282

Diaphragm: contraction flattens diaphragm, responsible for 75 percent of air moving into lungs during quiet breathing External intercostal muscles: move the rib cage outwards and upwards During quiet breathing only inspiration is active (you need the diaphragm to flatten and you need the intercostal muscles to contract) Since air is moving along is pressure gradient it is passive on the exhale in quiet breathing.

Answer 283

Scalenes: Pectoralis minor, sternocleidomastoid, erector spinal muscles: Help the external intercostal muscles elevate the ribs. Forced expiration: Internal intercostal muscles, transversals thoracis -depress ribs and reduce width and depth of thoracic cavity. Abdominals, int/ext obliques and altissimo dorsi -assist internal intercostals by compressing abdomen, forcing diaphragm upwards (during sneezing, coughing, singing) quiet breathing: diaphragm and external intercostal muscles Quiet expiration: none Forced inhalation: Forced exhalation:

Answer 284

It is a dome shape, it flattens upon inhalation to allow air in, and moves up to dome shape again on exhalation.

Answer 285

The rate of air flow that the alveoli encounter during normal breathing. Therefore, it determines the amount of oxygen and carbon dioxide that are exchanged in the alveoli The higher the alveolar ventilation rate, the higher the blood O2 concentration and the lower the blood CO2

Answer 286

Tidal volume (TV)- 500ml Is the amount of air inhaled/exhaled in one breath during quiet breathing.

Answer 287

IRV is 3000ml | And is the maximum amount of air that can be forcibly inhaled after TV

Answer 288

1200ml | Is the maximum amount of air that can be forcibly exhaled after TV

Answer 289

1300ml Is the amount of air left in the lungs after maximal expiration (ensures that the alveoli don’t collapse)

Answer 290

4700ml Is the maximum amount of air that can be forcibly exhaled after maximum inspiration Total lung capacity (TLC)- 6000ml Is the maximum amount of air the lungs can contain

Answer 291

The air that gets sucked into the respiratory system but does not actually participate in gas exchange They are in the airways Nose/nasal cavity Pharynx Trachea Bronchi 500 ml tidal volume, 150 not available for gas exchange (so of it still stuck in varies passages)

Answer 292

You take in a higher tidal volume than normal to compensate for the dead space that is also in the snorkel.

Answer 293

By changing blood flow: Increasing or decreasing vessel diameter —>changes the amount of oxygen delivery Changing the depth and rate of respiration: Increasing or decreasing frequency or depth of breathing —> increased or decreased oxygen consumption.

Answer 294

The respiratory centre is located in the brain at the medulla oblongata and pons. Involuntary* - regulate respiratory muscle - in response to sensory information i. e exercise causes involuntary changes to breathing through chemo receptors that detect chemical changes, detect the chemical amount in the blood in this case detecting levels of carbon dioxide in blood and refer back to the brain, brain then determines what to do Voluntary centres* -in cerebral cortex and medulla oblongata and pons -can bypass respiratory centres by activating motor neurons that control respiratory muscles. For example when swimming you need to override those signals

Answer 295

Changes in patterns of respiration induced by sensory input: Chemoreceptors: are sensitive to Co2 and O2 levels in blood or cerebrospinal fluid Constantly detecting chemical composition in the blood and sends to brain Baroreceptors: in aortic arch or carotid sinuses are sensitive to changes in blood pressure (Detects pressure) Stretch receptors that detect blood pressure Located in the carotid sinus and aorta Sends input to respiratory centres (when blood pressure falls respiration increases —>maximise oxygen levels in the blood) Irritating physical or chemical stimuli: in nasal cavity, larynx or bronchial tree (cough/ sneeze reflex)

Answer 296

High levels of co2 How to fix it? Breath. Stimulates the respiratory centre to increase depth and rate of respiration -relaxes smooth muscle in arterioles and capillaries —> increases blood flow—> increases oxygen delivery and carbon dioxide removal

Answer 297

Percentage of the partial gas x 760 mmhg (atmospheric pressure) I.e nitrogen in air is 78.6 Therefore 78.6 x 760 = 597mmHg I.e oxygen is 20.9 percent of build of air x by 760mmHg roughly 159mmHg

Answer 298

Humidified Exchanged gasses with blood Mixed with residual air Partial pressure goes down because you’re mixing it with residual air (old air) that has less oxygen etc in it

Answer 299

Gas occurs between air in the lungs and blood in the capillaries through membranes Gases diffuse down their concentration gradients The amount of gas that dissolves in water is determined by it solubility in water and its partial pressure in air

Answer 300

Pulmonary ventilation: the breathing in and out of air. Eternal respiration: occurs between the lungs and the blood, and is the exchange of oxygen for carbon dioxide between the alveoli and the blood Blood gas transport: transport of o2 and co2, between the lungs and the tissues Internal respiration: exchange of gases (o2 and co2) between blood and the tissues

Answer 301

Because the partial pressure of oxygen is lesser in the blood than in the alveoli so it moves down its pressure gradient. Similarly with oxygen moving from blood to tissues its always going to move from high to low, with happens with carbon dioxide as well.

Answer 302

The vast majority of oxygen in your blood is bound by haemoglobin, haemoglobin is found in your red blood cells, so red blood cells job is to carry the oxygen. Each haemoglobin is capable of binding to 4 haemoglobin molecules

Answer 303

pH(acidity of the blood): the lower the pH (increased acidity), the lower the oxygen binding affinity A working muscle requires a lot of oxygen to work and carbon dioxide is a byproduct of oxygen so therefore would produce a lot of co2. Carbon dioxide makes the blood acidic. Associated with acidity. The more work a muscle does the higher amounts of carbon dioxide it produced, the tissue becomes slightly more acidic therefore tissues have a higher affinity for carbon dioxide and therefore higher acidity. Oxygen dissociates with the haemoglobin when blood reaches these tissues. So when blood arrives at a location that is slightly more acidic blood will jump off the haemoglobin and into the tissue. Temperature: The lower the temperature, the higher the oxygen binding affinity (the oxygen will bind to the haemoglobin better) I.e oxygen will bind to haemoglobin better in cold temperatures than warm temperatures Oxygen dissociates with Hb more readily at metabolising tissue during exercise. Concentration gradient: oxygen will move off of heamoglobin into tissue to follow its concentration gradient

Answer 304

90 percent transport as a carbonic acid: Co2 + h2o —>H2CO3 —> HCO3 + H(+) Carbon dioxide + water —> carbonic acid —> bicarbonate + hydrogen ion 5 percent transport as carbaminohaemoglobin (HbCO2) bind to amino group of Hb 5 percent dissolves as gases

Answer 305

An alteration in the blood ph, because a change in carbon dioxide results in a change in pH in the blood therefore the chemoreceptors are detecting a change pH in the blood.

Answer 306

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Answer 307

If the chemoreceptors detect too much co2 in blood it may hypoventilate to expel co2 from the body Oxygen usually has little effect not a major stimulus however when the blood partial o2 is lower than 60 mmHg, this can significantly stimulate ventilation High altitudes after several days—> because the air has such little oxygen

Answer 308

Low oxygen levels Causes: hypoxemix hypoxia Usually due to inadequate pulmonary gas exchange Ischemic hypoxia: inadequate circulation Anemic hypoxia: anemia Signs: cyanosis : blueness of skin

Answer 309

Damages tissues, destroys enzymes, leads to seizures, coma and death.

Answer 310

To remove metabolic waste from circulation. Metabolic waste refers to —> urea, creatinine both products of protein metabolism Also in the waste: Water, ions, drugs Removing these substances from the blood

Answer 311

Produced in kidneys Moves down the ureter (one from each kidney) towards the urinary bladder Urinary bladder: temporarily stores urine prior to elimination Urethra: conducts urine to exterior; in males transports semen as well.

Answer 312

Filter blood, anything which is considered as waste we lose as urine. *forms and expels urine* Hydrogen-which makes your blood more acidic Bicarbonate which makes it more alkaline If the blood is too acidic or too alkaline it will interfere with metabolism (interfere will cells ability to work) Renin: hormone released by the kidneys and plays a part in loving term regulation of blood pressure Erythropoietin: when the kidneys detect that they don’t have enough oxygen, they release this hormone to produce more red blood cells. Vit D: helps with calcium absorption. Role in BP maintenance

Answer 313

The hilum is the entry and exit point for your nerves and your arteries and the exit point for veins and ureters from the kidneys.

Answer 314

Renal fascia: Outer layer of the kidney, it is connective tissue to anchor Adipose capsule: Fatty tissue Holds organ in place Protects against trauma Renal capsule: Inner most layer that lines the kidneys Also protects the kidneys against infection and trauma Doesn’t allow for much stretch, so if it becomes inflamed you will feel pain.

Answer 315

Renal Cortex: -outer zone The majority of nephrons are located in this cortex To the renal medulla To the minor and major calyx To the renal pelvis To the ureter

Answer 316

- functional unit - consists of corpuscle (a capsule and capillaries) and collecting ducts - blood is filtered to produce urine - adjust levels of nutrients and wastes in blood by reabsorption and secretion, filtration As a result of filtration you produce filtrate

Answer 317

Filtration, reabsorption and secretion Filatration substances are going from capillaries to the capsule, forming filtrate. Reabsorption: returning substances back into the blood Secretion: taking substances out of the blood and putting them into the nephron

Answer 318

Each nephron does not have its own collective duct, many nephrons use the same collecting duct.

Answer 319

Capillaries

Answer 320

Aorta/renal artery—>smaller arteries—>afferent arterioles(feed into nephron)—>(supplying blood to the capillaries) glomerulus—>efferent arterioles (exit the nephron) —>peritubular capillaries (surround your tubules) —>(from there we send blood to venules-smallest of veins) venules—> medium sized veins—> renal vein Cortical radiate arterioles branch into afferent arteriole because that’s what it divides into, and supplies your nephrons Microcirculation ——————— Afferent arteriole ENTERS glomerulus -blood is filtered Efferent arterioles LEAVES glomerulus (smaller in diametre than my afferent to create pressure and allow for filtration to occur) Peritubular capillaries delivers blood to venules -at the peritubular capillaries SECRETION, REABSORPTION

Answer 321

Muscular tubes, smooth! Their walls have 3 layers epithelium,muscle and connective tissue Attached to abdominal wall Transport urine form renal pelvis to bladder -peristalsis are ways of contractions which push urine along so that we can store it

Answer 322

Hollow, distension muscular sac waiting to be filled with urine Located in the pelvic cavity 500ml of urine, time to go to the bathroom! Walls contain: Epithelium, smooth muscle (detrusor) -will contract when i want to push urine along, but will relax to store urine Storage of urine -SNS stimulation of detrusor =relaxation, storage, Parasympathetic which is going to make the detrusor contract Internal urethral sphincter is a continuation of the detrusor and is involuntary, the parasympathetic is going to make it relax and opens it. External urethral sphincter which is under voluntary control—> somatic make the muscle contract, so we lift that stimulation of the somatic nervous system to allow us to urinate

Answer 323

A female because the urethra is shorter and closers to the anus therefore bugs are easier to ascend

Answer 324

Kidney pyramids Minor calyces Major calyces Renal pelvis Feeds into Ureters *Sphincters* control release of urine Bladder Urethra

Answer 325

The process of voiding urine Parasympathetic contraction of detrusor muscles of urinary bladder Parasympathetic relaxation of internal urethral sphincter Somatic relaxation of external urethral sphincter

Answer 326

Nephron Two types: Cortical and juxtamedullary (Most of ours are cortical) Consist of: Renal corpuscle -glomerulus and Bowman’s capsule Renal tubule- PCT -proximal convoluted tubule, loop of Henle, DCT- distal convoluted tubule Collecting duct- many nephrons emptying into the same collecting duct

Answer 327

Secreted by anything that increases in loss | - fever, burns, vomiting diarrhoea, haemorrhage

Answer 328

Inside cell ————— Potassium (k+) Proteins (-ve) Phosphate (HPO42-) Outside cell _____________ Sodium (na+) Chloride (Cl-) through sweat etc we lose fluid, we need to replenish this fluid through food and water

Answer 329

A solute is anything that is dissolved in water The majority of solutes are electrolytes so ions The ratio of solids: water Number of solutes per ml More solutes= concentration Less solutes= dilute Need to draw water from somewhere to put in the plasma

Answer 330

Specific gravity is the ratio of density of a substance to the density High SG ———- ``` Urine concentrated More solutes in each ml Low SG ——— Urine dilute Less solutes in each ml ```

Answer 331

Needs to be a balance between - sodium gained through GIT - sodium lost through urine and sweat Sodium must be replaced for neural activity (action potential) If highly concentrated sodium in blood water will be drawn towards it

Answer 332

Renin is released—> turns angiotensinogen into angiotensin 1 —> ACE (enzyme, conversion occurs in lungs) coverts angiotensin 1 into angiotensin II Angiotensin II : cause vasoconstriction (going to force driving pressure to increase) causes posterior to release ADH (which increases water in blood) Causes the release of aldosterone from the adrenal gland which increases reabsorption of sodium and H2O Lastly in BP is low, blood volume is low which stimulates sensors in hypothalamus which is going to make you feel thirsty, so stimulates thirst

Answer 333

We begin in the cortex of the kidney Inside the cortex are nephrons Blood is arriving to the nephron through the afferent arteriole In travels into the glomerulus (capillaries) We get filtration because the afferent arteriole is larger than the efferent arteriole causing a net filtration pressure Our solutes, water are passed through into the Bowen’s capsule Anything that doesn’t filter into the bowmen capsules continues along through the efferent arteriole (Inside the capsules) Travels through the PCT and the loop of Henle= the major process that happens in these areas is reabsorption which means return to the blood Continue to the distal up to the collecting duct=major process happening here is secretion and hormones target these areas. These hormones are dependant on hydration status. If dehydrated they come along. I.e not enough salt aldosterone reacts. Now the filtrate arrives at the collecting duct, final composition of urine goes down the collecting duct The collecting duct is in the medulla, from the medulla urine makes its way to the minor calyx, into the major, into the renal pelvis then into ureters to be stored in the bladder. To release this urine its the parasympathetic nervous system that opens up the sphincters to release urine to the external via the urethra.

Answer 334

The digestive tract is a hollow tube starting at the mouth and ending at the anus

Answer 335

Beings in esophagus (which is a hollow collapsed tube, smooth muscle tissue) Down into the stomach which churns the food into small enough particles into chime From there its emptied into the small intestine Makes its way into the large intestine Then released from anus

Answer 336

Accessory organs= contents don’t actually pass through but are vital for digestion. I.e salivary gland

Answer 337

Ingestion -intake of food Mechanical processing -crushing, tearing, churning Chemical digestion -chemicals breakdown of molecules (carbs, proteins, fats) Secretion -water, enzymes, acids, etc Absorption -uptake nutrients into blood/lymph Excretion -elimination of undigested material Mechanical breaks it down into chunks so that chemicals can come and make them even smaller

Answer 338

Inner layering: mucosa=a mucous membrane, epithelial tissue with goblet cells that secrete mucous Under mucosa is the submucosa which contains blood vessels Under that is the muscularsis (circular, and longitudinal) externa And under that is serosa membrane (thin membrane which covers organs)

Answer 339

Epithelial- mucosa (inner layer) Connective layer -submucosa followed by muscle layer Followed by serosa The MUCOSA Is the inner lining of the digestive tract The SUBMUCOSA Is a layer of dense, irregular connective tissue Has large blood vessels and lymphatic vessels ``` The Muscularis Externa Is dominated by smooth muscle cells Are arranged in: Inner circular layer Outer longitudinal layer ``` The serosa Serous membrane covering muscularis externa (Secrets serous fluid to keep everything lubricated and intact)

Answer 340

``` Occurs at: the mouth -mastication (chewing) -deglutition (swallowing) *don’t have to use these words* ``` Esophagus (minimal mechanical processing) Once it passes throat it becomes involuntary because the smooth muscles take over -the process is called peristalsis Stomach -mixing and churning etc

Answer 341

The teeth Incisors: -bitting, cutting Canines: -tearing, shredding Molars: -crushing, grinding

Answer 342

**JUST KNOW mouth’s job is to chew the food and mix the food with salvia*** Requires little thought (partly involuntary, can over ride, put food in mouth and not chew) Teeth: Checking, grinding motion to break down large food particles into small enough pieces to be swallowed; first step in mechanical processing Increased the surface area of food particles that can come into contact with digestive enzymes. Tongue: (And buccinator and obicularis oris muscles): ***don’t need to memorise*** Manipulates food between teeth (i.e pushing food against teeth, mixing with saliva, forming bolus) Palate: - separates the oral cavity form the nasal cavity - rough surface, helps younger manipulate food

Answer 343

The throat is a common passageway for solid food liquids and air

Answer 344

Inferior to the pharynx and posterior to the trachea, located in the mediastinum Tube from the throat to the stomach goes through the diaphragm and is connected to the stomach. The lower esophageal sphincter (LES) prevents food from the stomach re-entering the esophagus.

Answer 345

Swallowing - can be initiated voluntarily - proceeds automatically Divided into 3 phases - buccal phase - pharyngeal phase - esophageal phase

Answer 346

A strong wave of muscular contractions that pushes food (bolus)down into the stomach

Answer 347

The approach of the bolus triggers the opening of the lower esophageal sphincter which normally remains closed to keep the stomach acid in the stomach.

Answer 348

Is a j shaped bag 50ml when empty, stretch up to 4 litres. At the onset of deglutition (point of swallowing) swallowing centre sends messages to relax stomach in preparation of receiving food. Arrival of food imitates the receptive-relaxation response. Pacemaker cells in the muscularis externa initate stomach contractions ~ everything 20 secs After 30 mins, pace picks up and contracts with more force —> churning, mixing, breaking up food

Answer 349

Because you don’t have to think about it

Answer 350

Plays a key role in digestion and absorption of nutrients 90 percent of nutrient absorption occurs in the small intestine, now

Answer 351

The pulpy acidic fluid which passes from the stomach to the small intestine, consisting of gastric juices and partly digested food.

Answer 352

The segment of the small intestine closest to the stomach Its the mixing bowl which receives chyme from the stomach and digestive secretions form pancreas and liver. Functions: The receive chyme from the stomach To neutralise acids before they can damage the absorption of the small intestine

Answer 353

Is the middle segment of small intestine It is the location of most of the chemical absorption and nutrient absorption

Answer 354

The final segment of the small intestine A sphincter that controls flow of material from the ileum into the caecum of the large intestine

Answer 355

Mixes chyme with intestinal juices, bile and pancreatic juice Churns chyme to increase contact with mucosa for absorption and digestion Moves reside towards large intestine **similar to preristalsis expect moves food forwards and backwards rather than forward only creating more time for digestion and absorption

Answer 356

Because its really really long so content stays in there for a sufficient amount of time for digestion and absorption, also there is the ville which increases the surface area for absorption

Answer 357

Final absorption of remaining water Reduces the residue of a meal into faeces The caecum, the colon, the rectum Functions: Reabsorption of water Compaction of intestinal contests into faeces Absorption of important vitamins produced by bacteria Storage of faecal material prior to defecation

Answer 358

``` Internal sphincter (smooth muscle) External sphincter (skeletal muscle) ``` Both need to be relaxed in order to go to the toilet

Answer 359

Defecation reflex in stimulated when rectum is stretched, it involves 2 reflexes: The intrinsic defecation reflex - operates entirely within the myenteric plexus (i.e does not need the CNS) - stimulated when the walls of the colon are stretched causes the internal sphincter to relax of course it can be overridden. The parasympathetic defecation reflex - stretch in colon sends signals to the spinal cord - response: intensify peristalsis and relax internal sphincter Positive feedback Stretch sends messages to brain, brain sends messages to cause more contract contract sends messaged to brain continues until feaces is eliminated

Answer 360

1. Parotid salivary gland 2. sublingual salivary gland 3. Submandibular salivary gland

Answer 361

-Lubricating/ cleansing the mouth -Keeping pH around 7.0 -moistening, lubricating and combining materials in the mouth -dissolving chemicals that stimulates taste buds and provides sensory information -dilute and rinse away strong tastes/toxins Initiating digestion of complex carbohydrates by the enzyme ***The salivary glands produce salivary amylase (enzyme) these enzymes work to break down food, lingual lipase is released but is not working yet***

Answer 362

Triggered by thought , smell, chewing action, presence of food etc Parasympathetic input: Large amounts of watery saliva Sympathetic input Reduced amounts (dry mouth) Saliva is thick and contains more mucous

Answer 363

Also contains chemical digestive agents Very acidic =pH of 1.5-2.0 Lining of the stomach contains gastric glands (glands that secrete things) Parietal cells: (secrete Hydrochloric acid) (HCI) which is an intrinsic factor HCI= kills microbes Denatures proteins (and enzymes) Breaks down cell wall and connective tissue Activation of pepsin Why it important to make hydrogen and choline separately? Put together in the stomach to make HCI but must be made in the stomach so they don’t start damaging or denaturing the cells. Chief cells: Secrete pepsinogen (anything with Ogen is an inactive form of a protein) Pepsinogen is activated into pepsin by the the HCl (need an acidic environment to activate pepsinogen into pepsin) pepsin is a powerful enzyme which digests proteins into smaller proteins (polypeptides) Once activated pepsin digests protient

Answer 364

Stomach epithelium secretes alkaline salts into mucous lining to protect underlying tissues Epithelial cells that line stomach have a high turnover rate Epithelial cells are tightly packed close together

Answer 365

The brush border of the small intestine release enzymes: Maltase, sucrase, lactase Maltase digests maltose Sucrase digests sucrose Lactase digests lactose Enteropeptidase - activates the pancreatic trypsinogen - breaks down materials in contact with brush border for absorption

Answer 366

2 oval shaped organs enclosed in a fibrous capsule called tunica Albugenia Divided into compartments which contain seminiferous tubules site of sperm production Sustenacular cells protect nourish and rpmote sperm development Also secret the hormone inhibin Interstitial (leydig) cells- testosterone production

Answer 367

Proteins have to be broken down into amino acids before they can be absorbed Carbs have to be broken down into monosaccharides Fats have to broken down into fatty acids before they can be dissolved into the lymph

Answer 368

Movement of organic substances, electrolytes, vitamins, and water across digestive epithelium into interstitial fluid of digestive tract

Answer 369

Blood collected form stomach, small intestine and large intestine travels first to LIVER (not heart)

Answer 370

Amylase does the course digestion of starch into oligosaccharides, and then brush border enzymes break it down further into single sugar rings Most of the carbs we eat are in the form of starch Starch(oligosaccharides) —> firstly broken down in the mouth by salivary amylase (50%) (Process stops until it reaches agin the pancreas) —> then in the small intestine by pancreatic amylase (50%)

Answer 371

Single sugared rings called monosaccharides, they are the only ones that can be absorbed Complex sugars i.e starch and glycogen are still too large, even disaccharides are too large to be absorbed, only when the brush border enzymes to digest the disaccharides into monosaccharides to be absorbed

Answer 372

Glucose and galactose are absorbed into cells via sodium-glucose transport protein (job to transport molecules into and out of the cell) Fructose is absorbed via facilitated diffusion

Answer 373

Carbs get broken down into monosaccharides and get absorbed into the capillaries Proteins get broken down into the amino-acids and they get absorbed into the capillaries Fats get broken down, but even in most basic form get absorbed by lymph first

Answer 374

A type of lipoprotein that is made of cholesterol mainly It delivers cholesterol to body cell Its a bad cholesterol -causes blockages etc The low density lipoproteins have less proteins and more fat (cholesterols) where as high density lipoproteins have equal amounts of proteins and cholesterol, and carry excess cholesterol from periphery back to the liver LDL back HDL good

Answer 375

Absorption is less than 10 percent Mainly for reabsorption of water and bile salts —in the caecum and transported in blood to the liver Absorption of vitamins produced by bacteria Absorption of organic waste

Answer 376

Cells cannot actively absorb or secrete water All movement of the water across lining of digestive tract : Involves passive water flow down osmotic gradients

Answer 377

Metabolism refers to all of the chemical reactions that occur in our bodies It is the balance between catabolic reactions and anabolic reactions Catabolism: Breaking down large molecules into smaller collected which releases energy for ATP production Anabolic: Building larger molecules from smaller, this requires energy (in the form of ATP)

Answer 378

The thyroid hormone which is secreted in the thyroid gland Used for increasing metabolism by binding to mitochondria to increase ATP production Which then influences genes that increase metabolic rate

Answer 379

ATP: adenosine triphosphate ATP is a molecule of stored energy which the cell can break down from ADP ADP is phosphorylated and becomes ATP ATP is dephosphorylated and becomes ADP in the process energy is released (for growth, mitosis, muscle contractions, sodium potassium pumps etc)

Answer 380

Minimum resting energy expenditure of an awake, alert person Measured in calories If you eat less than what you expend then you’re going to lose weight If you eat more than what you expend you’re going to gain weight Influenced by hormones Sympathetic nervous system increases rate of metabolism Adrenaline, noradrenaline (stress) increases BMR Speeds up body temperature Increased temperatures speed up metabolism Higher BMR during fever

Answer 381

Is essentially glucose metabolism - Large polysaccharides are broken down into glucose, fructose and galactose - These are monosaccharides and are absorbed by the intestines - The liver converts fructose and galactose into glucose Glucose is catabolised to yield ATP

Answer 382

ATP production -glycogen synthesis Glycogen - is lots of glucose molecules bound together to allow storage of glucose in muscles and liver What happens with excess glucose? You store it. Glucose as a single ring monosaccharide must be turned into glycogen in order to be stored

Answer 383

Carbohydrates—> broken down by amylase into monosaccharides —> absorbed into ATP if needed Or turned back into glycogen for storage Once its turned into glycogen it can be stored in the liver Once the liver is full you can store them in skeletal muscles If you still have too much to can convert it into amino acids And if still too much can covert it into fats

Answer 384

Glucose is absorbed by the intestines via secondary active transport (hitch-hikes with Na+) Insulin works on fats cells, muscle cells and liver cells to absorb the glucose into the cell. So if you don’t have enough insulin the glucose stays in the blood and you end up with high glucose levels.

Answer 385

1: Glycolysis 2: Anaerobic fermentation 3: aerobic respiration You need to know how many molecules at the end of catabolism are released:

Answer 386

Glyco=glucose Lysis=break down All i need to know: At the end of glycolysis there are 2 ATP molecules ***The first step in glucose breakdown*** you get the glucose molecule and break it * **releases 2 molecules of ATP*** * **releases 2 molecules of Pyruvic acid***

Answer 387

Glycolysis: 2 ATP Kreb’s cycle: 2 ATP Electron transfer: 34 ATP TOTAL YIELD: 38 ATP So from one glucose molecule can yield 38 ATP molecules

Answer 388

Glucose as a monosaccharide cannot be stored, must be polymerised into glycogen first Formation of glycogen for storage occurs in the liver and skeletal muscles This process is call glucogenesis Glycogenesis= Glyco=glycogen Genesis=synthesis

Answer 389

Fats, some are used for structural purposes eg phospholipids belayer membrane Lipolysis= lipid breakdown Lipogenesis= lipid synthesis Occurs in the liver Stimulated by insulin

Answer 390

Proteins are broken down by HCI (hydrochloric acid) and pepsin in the stomach and absorbed as amino acids by the intestines as ATP and synthesis of proteins Proteins—> polypeptides—> dipeptides —>amino acids Pepsin is the enzyme that converts proteins into polypeptides and then protease converts it into dipeptides then peptidases that turns it into amino acids Excess amino acids can be used as glucose which is then broken down into glycogen Excess amino acids can be stored as fat

Answer 391

Amino acids are absorbed by the intestines, then diffuse into the blood stream and transported into cells via active transport Proteins can function as: ``` Enzymes Transportation i.e haemoglobin Antibodies Clotting factors i.e Fibrinogen Hormones Structural components i.e collagen ```

Answer 392

Protein is not generally a good way for the body to store energy Therefore we only break proteins down under special circumstances Liver can convert amino acids into fatty acids or glucose During starvation the body can break down proteins to get amino acids i.e muscle —> amino acids—> glucose

Answer 393

Occur at ribosomes, require energy input. | They put all the amino acids together and turn them into proteins

Answer 394

Insulin Released in response to high blood glucose levels (eg after a meal) Glucagon Released when blood glucose levels drop (eg between meals/ fasting/ exercise etc) Adrenaline Promotes glycogenolysis and lipolysis (break down of lipids and glucose) under stress conditions Cortisol Released under stress situations. Promotes fat and protein breakdown and gluconeogenesis

Answer 395

How the drug works vs how our body affects the drug

Answer 396

The condition in which the drugs prescribed or used for Contraindications is what not a drug is used for Common drug interactions

Answer 397

Chemical name Approved or generic name e.g diazepam (this name is derived from the chemical structure of the drug it is the active ingredient) Trade name i.e proprietary or brand name e.g Valium Generic prescribing

Answer 398

Passage of a drug from its site of administration into the plasma Drug must cross cell membranes What determines drug absorption? Nature of the absorbing surface so how many cell membranes What’s the surface area like, what’s the blood supply like Also the chemical structure of the drug (i.e are they small? Lipid soluble? Not charged not ions)

Answer 399

Transfer of drug between locations (via blood) Many drugs exist in circulatory system bound to plasma proteins Only “free” drugs exert pharmacological effects

Answer 400

Enzyme modification of drug molecules Start of the elimination process Metabolism of drugs by the liver renders drugs hydrophilic (not lipid soluble) Bioavailability* Amount of drug that is available to the body to produce a therapeutic effect Expressed as a %

Answer 401

Getting the drug out of the body | Irreversible loss of unchanged drug or metabolite from body i.e urine

Answer 402

1. Carrier molecules 2. Enzymes 3. ion channels 4. Receptors Receptors are a large group of proteins that are drug targets Chemical signalling between and with cells What’s a ligand? A molecule that binds to receptors How do drugs act on receptors “Lock and key analogy” specific Either binds as an agonist or antagonist

Answer 403

Ketones are produced ink your liver, | You produce them when you done have enough insulin in your body to turn sugar into energy