BIOL 104 Flashcards
Anatomy
The study of the structure of an organisms parts
Physiology
The study of function.
What tissue covers the surface of the body and lines organs?
Epithelial
What tissue has the highest cancer rate and why?
Epithelial tissue amounts for about 80% of cancers.
It is being continuously renewed so higher risk in cell division.
What are the physical challenges for the human body to maintain homeostasis when climbing Everest?
Thermoregulation
Blood glucose regulation
Blood oxygen regulation
Osmoregulation (fluid concentration)
What makes up tissues?
Specialized cells that work together.
What are organs composed of?
Multiple tissues coordinate to create a functioning organ.
What is the normal blood pressure range for a human?
90-120 systolic
60-80 diastolic
How long do RBC’s live?
120 days
What cancer treatment has a 100% remission in recent test?
Immunotherapy
What percentage of whole blood is made up of blood cells?
45% and 55% plasma
What is connective tissue and what is the most common type?
Supports and joins other tissues
Most common is loose connective tissue which binds epithelia to underlying tissue.
Cartilage
Forms a strong flexible matrix
Has no blood cells so heals slow.
Fibrous connective tissue
Has a dense matrix of collagen which forms tendons
What type of tissue is bone?
Bone is a rigid connective tissue made of a dense matrix of collagen fibres hardened with calcium salt deposits.
What is adipose tissue and what does it do?
A type of connective tissue that stores fat and works to insulate and cushion.
Is blood a tissue?
Yes, blood is a special type of connective tissue that is suspended in plasma with its main function being transport of substances.
What are the three types of muscle tissue?
Skeletal - Moves your skeleton, attached by tendons, humans are born with most muscle fibres.
Cardiac - Found only in heart tissue, responsible for pumping of the heart.
Smooth - Found in many organs as well as blood cells, can contract slowly over time.
Nervous tissue
Found in the brain and spinal cord as well as in nerves that connect these organs.
Convey info through electro transmissions.
Basic unit is a neuron or nerve cell.
What are some organ systems?
Skeletal, reproductive, urinary, muscular, digestive, endocrine, nervous, lymphatic, circulatory, respiratory, integumentary.
Homeostasis
The tendency to maintain constant conditions in an internal environment despite external changes.
Basic principle of negative feedback?
The result of a process inhibits said process.
Hypoxia
Low level of oxygen in blood
What homeostatic mechanism controls temperature?
Thermoregulation
Basic principle of positive feedback?
The result of a process intensifies said process.
The release of oxytocin during labour is an example of a positive feedback loop.
Endotherms vs Ectotherms
Endotherms maintain a body temp warmer than the surrounding environment (mammals)
Ectotherms obtain their body heat by absorbing it from their surroundings (reptiles, fish)
How does the body react to being too cold or too hot?
Sensors in skin detect temperature, sending signals to the hypothalamus which sends signals to effectors.
If too cold blood vessels near the surface constrict and muscles contract to cause shivering.
If too hot blood vessels dilate and sweat glands active allowing evaporative cooling.
Why is a moderate fever a good thing when sick?
A moderate fever discourages bacteria and the increase in body temp speeds up internal defences.
Osmoregulation
Control of the gain or loss of water and dissolved solutes.
How does blood enter and exit the kidneys for filtration?
Enters through the renal artery and leaves in the renal vein.
What organ regulates glucose levels?
Pancreas
Glucagon increases blood sugar
Insulin decreases
What is the composition of human urine?
94% water
3.5% urea
1% chloride
0.5% sodium
What are nephrons and how many are their?
Nephrons carry out the processes of filtration.
Each kidney has about a million.
Filtration
Blood pressure forces water and solutes from blood through a filter at start of nephron tube.
Creates filtrate
Reabsorption
As filtrate passes through the tubules water and nutrients are reabsorbed into the blood stream.
Secretion and Excretion
The filtrate becomes more concentrated with waste and results in urine.
Urine leaves the nephrons and collect in the kidneys before leaving via ureter and stored in bladder.
Water balance and homeostasis process
If blood pressure is high and their is a large amount of water in blood receptors detect high BP and the hypothalamus decreases ADH release into blood. Decreased ADH tells the kidneys to allow more water to be excreted in urine.
If BP is low receptors detect this and the hypothalamus increases ADH release into blood telling the kidneys to retain more water diluting solutes in the blood and increasing BP.
ADH released from posterior pituitary in response to hormone from hypothalamus.
Hypothalamus
Releases hormones that controls the pituitary gland which is responsible for creating hormones.
Pituitary gland
Creates and secretes hormones into circulation.
What secretes female sex hormones?
Ovaries
Thyroid and parathyroid glands
Thyroid regulates metabolic processes
Parathyroid regulates blood calcium levels.
Adrenal gland
Triggers flight or fight response, cortisol levels.
Artery structure and function?
With the exception of the pulmonary blood vessels, arteries carry oxygenated blood away from the heart.
Arteries branch into arterioles as they approach organs then into capillaries.
Vein structure and function?
Veins carry deoxygenated blood back to the heart.
Capillary structure and function?
Capillaries have thin walls allowing exchange between blood and interstitial fluid.
Capillaries transfer material to and from surrounding tissues .
As blood flows from capillaries it enters venles which converge into veins.
Pulmonary circuit vs Systemic circuit
Pulmonary circuit flows between the lungs and the heart
Systemic circuit flows between the heart and the rest of the body.
Atherosclerosis
Disease that restricts blood flow in vessels.
Accumulation of fibrous plaque.
HDL vs LDL
HDL is considered good cholesterol and is easily removed from the circulation and processed in liver.
LDL is bad cholesterol and tends to build up in the walls of arteries.
Foods high in saturated fat contribute to high LDL and low HDL.
Right atrium
Two large veins pump O2 poor blood into the right atrium, which is then pumped into the right ventricle.
Right ventricle
Right ventricle pumps O2 poor blood to the lungs via 2 pulmonary arteries.
Left atrium
O2 rich blood travels through the pulmonary veins into the left atrium. Which is then pumped to left ventricle.
Left ventricle
O2 rich blood is pumped from the left ventricle via the aorta which pumps blood to the body.
Where does O2 poor blood from the head go?
It is channeled into the superior vena cava to return to the heart.
Where does O2 poor blood from the legs go?
It is channeled into the inferior vena cava and returned to the heart.
What is a healthy resting heart rate?
60-100 bpm
One heartbeat takes approximately 0.8 seconds what happens in those 0.8 seconds?
The first 0.4 seconds is diastole where the heart relaxes and blood flows into the four chambers.
The first 0.1s of systole the atria contract pushing all blood into the ventricles.
The last 0.3s of systole ventricles contract pushing blood into the aorta and pulmonary arteries.
What is the hearts pacemaker and how does it function?
The Sinoatrial node is made up of specialized tissue in the wall of the right atrium that generates electrical impulses.
These impulses cause the atria to contract then pass to a relay point that delays the signal allowing the atria to empty before the ventricles contract.
What can cause the sinoatrial node to beat faster?
Caffeine, epinephrine, adrenaline, exercise.
What lines blood vessels?
A thin layer of epithelial cells.
What makes arteries and veins structure different from capillaries?
Arteries and veins have two additional layers; an outer layer of elastic connective tissue and an inner layer of smooth muscle that allows constriction and dilation of blood vessels to regulate flow.
Why can you feel your pulse?
When ventricles contract during systole blood is forced into the arteries faster than it can flow to atrioles stretching the arteries.
How does blood flow through veins?
Veins are sandwiched by skeletal muscles which contract and and squeeze blood along. Flaps act as one way valves to prevent blood flow in the wrong direction.
How much blood is in a human?
Around 5L
What are the three cellular elements of blood?
Red blood cells (erythrocytes), White blood cells (leukocytes), Platelets.
Why are RBC’s disc shaped?
To maximize surface area available for gas exchange
What is the purpose of RBCs?
Carry O2 from lungs to tissues.
Each RBC contains 250 million hemoglobin, which contain 4 heme groups with iron containing protein that transports O2.
What is anemia?
People who are anemic have low RBC counts or hemoglobin.
What happens if O2 levels in blood are low?
Specialized cells in the kidneys detect low blood oxygen levels and increase the production of EPO.
EPO tells tissue inside your bones (bone marrow) to make more RBC’s.
What element carries oxygen in the blood?
Iron which is found in the heme component of hemoglobin.
What genetic disorder causes excessive bleeding?
Hemophilia
White blood cells (leukocytes) structure and function?
Contain nuclei and other organelles.
Fight infection.
Can exit blood to fight local infections
Platelet structure and function
Bits of membrane enclosed cytoplasm that aid in clotting.
Form sticky clusters that adhere and seal damaged blood vessels.
Release clotting factors, molecules that convert fibrinogen to a thread like protein called fibrin which forms a dense network to create a patch.
What is an embolus?
A blood clot that forms then dislodges and travels elsewhere.
What is an angioplasty?
The insertion of a catheter with a balloon that is inflated to compress plaque and widen arteries.
Bypass
A vein from the leg is attached to a blocked artery allowing another pathway.
What happens externally when you inhale?
Chest cavity expands, rib muscles contract, diaphragm moves down decreasing air pressure in lungs and causing air to rush in.
What happens externally when you exhale?
Rib muscles and diaphragm relax causing ribs to contract and air pressure to increase forcing air out of the lungs.
What does smoking effect in the lungs?
Damages respiratory surfaces of the lungs and impairs alveolar function.
What happens in the naval cavity when you inhale?
In the nasal cavity air is filtered warmed and humidified by mucus and hairs.
What happens during inhalation after air passes the nasal cavity?
Air passes to the pharynx where digestive and respiratory systems meet.
What is the purpose of the epiglottis?
Leaf shaped flap in the throat that prevents food and water from entering the trachea and lungs. Stays open during breathing allowing air to enter the larynx.
Larynx function?
The larynx is the voice box.
Trachea structure and function?
The trachea is the windpipe which branches into bronchi leading to each lung.
What are bronchi?
Bronchi are large tubes that connect to the trachea.
Bronchi branch into finer tubes called bronchioles.
What are bronchioles and alveoli ?
Bronchioles are fine tubes that branch off from bronchi. Bronchioles end in grape like clusters of air sacs called alveoli.
Each lung contains millions of alveoli which are lined with epithelial cells and capillaries where gas exchange takes place.
Alveoli are not replaced after 20.
What influences heavier breathing?
Brain is influenced by CO2 content in the blood, more CO2 higher rate and depth of ventilation.
CO2 is a byproduct of cellular respiration.
Means of asexual reproduction?
Fission or fragmentation
Gametes vs Zygotes?
Gametes are sex cells with a single set of chromosomes
When an egg and sperm join they form a zygote.
When would an organism that can do both asexual and sexual reproduction choose to reproduce asexually?
When food and conditions are optimal.
When conditions are adverse they switch to sexual reproduction to produce genetically varied offspring with more potential for adaptation.
What are hemaphrodites?
Organisms with male and female parts.
Where do sperm cells develop?
Inside seminiferous tubules.
What are the stages of spermatogenesis?
Cells near the outer walls multiply by mitosis. Followed by meiosis 1 of a primary spermatocyte which produces two haploid secondary spermatocytes. Meiosis 2 forms four haploid sperm cells.
Where do sperm cells mature?
Epididymis
What is the raw material of evolution by natural selection?
Variation
How many erythrocytes per Microliter?
4-6 million
What is the path of sperm through the male system?
Testis —> Epididymis —> Vas deferens —> seminal vesicle —> sperm duct —> prostate gland —> urethra.
What makes up semen?
5% sperm 250-500 million sperm cells.
95% fructose, alkaline pH to protect sperm DNA and lubricant.
Where does semen enter sperm?
Prostate gland.
What does a vasectomy affect?
It cuts off the vas deferens.
What stimulates testosterone production and spermatogenesis?
Luteinizing hormone and follicle stimulating hormone are produced by the pituitary gland in. Response to hormones from hypothalamus.
What hormone stimulates development of sperm?
Testosterone
What hormone triggers ovulation?
Luteinizing hormone which is triggered by rising estrogen levels.
When do estrogen levels peak?
Day 12
When is the mature egg ovulated?
Day 14 following a peak in estrogen which leads to a spike in LH.
Where is LH and FSH secreted from?
Anterior pituitary
What happens if the mature egg is not fertilized.
Corpus luteum degenerates causing fall off of hormones.
Endometrium begins to shed causing menstruation.
What thickens the endometrium?
Rising levels of estrogen and progesterone.
What happens after fertilization?
If fertilized the embryo will develop into a blastocyst and embed itself in the endometrium and produce the hormone hCG, which prolongs estrogen and progesterone production by the corpus luteum.
What happens to the corpus luteum once the placenta develops?
Corpus luteum degenerates and the placenta beings to produce estrogen and progesterone.
Amnion
Fluid filled sac that encloses and protects the embryo.
First trimester checkpoints
End of month 1 brain and heart forming
End of month 3 fetus has facial features and internal organs
Can make a fist
2nd trimester
Continues to grow and develop including external genitalia
Teeth forming, bones hardening
3rd trimester
Becomes fully developed, gains majority of weight
Full term at 35 weeks
Most pregnancies last 38 weeks after fertilization.
What stimulates muscles to contract during child birth?
Oxytocin, contractions stimulate release of more oxytocin
What are the three stages of child birth?
Dilation: Time from onset of labor until cervix dilates to 10cm - 6 to 12 hours.
Expulsion: Period from full dilation to delivery. Strong contractions lasting a minute every 2-3 minutes
Typically 20 minutes to an hour.
Afterbirth: Delivery of placenta within 15 minutes of brith.
What hormone promotes milk production?
Prolactin
What are his tones?
Proteins used to package DNA
Nucleosomes
Consist of DNA wound around several his tones molecules
Chemotherapy
Full body treatment by toxic chemicals that kills all rapidly dividing cells
Radiation therapy
Using ionizing radiation to kill exposed cells by severely damaging DNA
Targeted therapy
Specific for cancer cells and not harmful for normal cells
Kills cancer cells by exploiting weaknesses of oncogenes or mutated tumor supresor gene
Immunotherapy
IMT uses antibodies two the immune system can recognize and kill the cancer cells.
Metastasis
Cancer cells spread through lymph and blood vessels to other parts of the body.
Stage 1
Tumor is small and has not grown outside organ it started in
Stage 2
Larger than stage 1 but has yet to spread
Stage 3
Tumour is large and has spread to nearby tissues and lymph nodes
Stage 4
Tumour has spread through the blood or lymphatic system to a distant site.
What are proto-oncogenes?
Normally promote cell division and differentiation but can be mutated and become oncogenes which are permanently activated.
Tumor supresor genes
BRCA1 and BRCA2 are both tumor suppressor genes. P53 is also another tumor suppressor gene.
Help prevent cells from growing and dividing too rapidly.
What causes Cystic fibrosis?
Caused by three nucleotides being deleted on chromosome 7.
