FINAL EXAM Y12 Flashcards
- How do you Write a hypothesis?
By using An if then statement. It should include both an independent variable (the factor you change in an experiment) and a dependent variable (the factor you observe or measure in an experiment) and it must be testable
What is an independent variable?
The factor you will change in an experiment
What is a dependent variable?
The factor you observe or measure in an experiment
What are controlled variables?
Controlled variables are quantities that a scientist wants to remain constant, and she must observe them as carefully as the dependent variables.
What is the difference between a control and experimental test?
The control is the thing you are comparing to and experimental is the things you are testing
What is the purpose of a control group?
It helps rule out alternate explanations of the experimental results.
Role of the placebo in an investigation
Something which tests is a the results from an investigation are psychological or not
What is quantitative data?
Quantitative research gathers data in numerical form which can be put into categories, or in rank order, or measured in units of measurement
What is qualitative data?
Qualitative research gathers information that is not in numerical form.
What ethical issues that might arise from investigation?
Things to consider to make sure that an investigation is ethics/ moral Ethical if: Voluntary participation Informed consent No risk of harm Confidentiality
Validity vs reliability
Validity: does the experiment test what it was actually supposed to test. how well experiment relates to the aim of the experiment.
Eg. Appropriate equipment for measurements, eliminates uncontrollable factors
Reliability: the extent to which an experiment gives the same result each time it’s performed (how close repeated measurements are to each other.)
Eg. Fixed control variables so all test carried out same, choice of equipment
Errors and limitations in data
Measurement errors
Surveys?
Surveys: a systematic collection, analysis and interpretation of information about a particular question or series of questions; usually designed so that data is collected from a large number of subjects.
Case study?
Case studies: an in-depth investigation of one particular person or situation
Longitudinal study?
Longitudinal study: a study concerned over a long period of time; may be carried out over years or decades
Secondary data?
Secondary data: data collected by someone other than people who are using the data
Define mean, median, range and probability
mean: average
median: middle number
range: the difference between highest and lowest measurements in a group
probability; the likelihood that a particular event will occur
Trends vs patterns?
trends: The general direction which something is developing or changing
patterns: Repeated pattern or sequence
What are confidence intervals used for?
confidence intervals can be used to predict the reliability of the data.
Where do independent and dependent variables go on a graph?
Dependent variable on vertical axis ( side) dependent variable on horizontal ( bottom)
Define immunity
Immunity: resistance to infection from invading microorganisms
Define immune system?
Immune system: different types of cells that occur in most organs of the body and that protect against foreign organisms, alien chemicals and abnormal cells
Define immune response
Immune response: a response triggered by foreign substances or microorganisms entering the body.
self antigen vs non self antigen
Self antigen: any large molecule produced in a persons own body ; does not cause an immune response in that person
Non self antigen: any compound foreign to the body that triggers an immune response.
Define infectious disease
Infectious diseases: Diseases caused by foreign organisms invading the body and multiplying there
Define pathogen?
Pathogen: A disease causing organism often referred to as a pathogenic organism
Define vector?
Vectors: An agent such as an insect capable of transferring a disease causing organism from one person to another
Infectious diseases can be caused by….
bacterial and viruses ( also fungi and animal parasites)
Physical characteristics of bacteria?
Physical characteristics of bacteria: single celled, seen only with a microscope, cell shape is used to classify into 4 catergories : cocci ( circular), bacilli ( rods), spirilla (loose coils) and vibrio ( curved rods)
Mode of action for bacteria?
Mode of action for bacteria: releasing toxins which inhibit/ alter cell activity or poisons which alter metabolism, they may also cause allergic reactions. Endotoxins- released when bacteria die, exotoxins- released by living bacteria.
Bacterial antigen- allergic/ immune response
Diseases caused by bacteria?
Diseases caused by bacteria: Chlamydia Cholera Gonnorrhoea Dental caries (tooth decay) Leprosy Pneumonia
Physical characteristics of viruses’
viruses
Physical characteristics: molecules of DNA or RNA, small, wrapped in proteins.
Mode of action for viruses?
Mode of action: DNA or DNA induce cell to manufacture more virus particles, attaching to the outside of a host cell allowing the nucleic acid to enter the cell, new viral genes are then produced by the host.
Diseases caused by viruses?
Diseases caused by viruses: HIV/AIDS, Bird flu Chickenpox Herpes Colds Ebola
Ways transmissionof pathogens can occur?
Direct:
Transmission by touch: direct and fomite(indirect)
Transmission by bodily fluids: through blood or other mucus membranes ( from nose, mouth, throat, genitals) eg. HIV, hepatitis b & c
Waterborne transmission: from drinking contaminated water or from droplets of moisture w/ pathogenic organisms are emitted when breathing, talking, sneezing or coughing eg. Influenza
Airborne transmission:moisture in exhaled droplets carry viruses and some bacteria
Ingestion: food or drink contaminated eg. Salmonella
Transmission of vectors: transfer of pathogens by other animals such as insects, ticks or mites. Some transfer directly others ( house flys) via food and water.
Forms of transmission by contact: direct( Touching an Infected person) or indirect (touching an object that has been touched by an infected individual, also known as fomite transmission )
Disease specific vectors- malaria> mosquitos
Define bacteriophage?
Bacteriophage:Viruses which multiply in bacterial cells causing death to the bacterium
Parasites.
Mode of action, physical characteristics and diseases
parasites
Diseases: Malaria, roundworms, lice
Physical characteristics:Multicellular, ecto and endo
Mode of action:Parasites cause infection by living and multiplying in another organism. This can cause fever, inflammation and other physical problems
Fungi.
Mode of action, physical characteristics and diseases
fungi
Diseases: ringworm
Physical characteristics: Multicellular, Eukaryotic
Mode of action: Reproduce by spreading microscopic spores, spores often found in air and soil where they can be inhaled or come in contact with body surfaces
Prions.
Mode of action, diseases and physical characteristics
Prions
Diseases: Mad cow disease
Physical characteristics: Folded protein structure
Mode of action: Prions are a type of protein that can trigger normal proteins in the brain to fold abnormally
Protozoa.
Physical characteristics, mode of action and diseases
Protozoa
Physical characteristics:Moves independently, single cellular
Modes of action: Produce toxin and multiply inside other cells
Disease: malaria
What are the 3 lines of defence?
First of defence: external barriers
physical + chemical barriers/ protective reflexes -> prevent entry into the body
Second line of defence: non specific internal defences
inflammation, fever, roaming macrophages-> destroy and remove pathogens if enter.
Third line of defence: specific internal defences
- antibody and cell mediated defences-> specialised lymphocytes target specific pathogens to destroy and remove from the body.
Outline external defence mechanisms of first line of defence?
skin: covers the outside of the body, stopping entry of microorganisms
Bacteria - huge number of bacteria live on the skin at a time????
Sebum- oily secretion secreted by the oil grands in the skin that kills some pathogenic bacteria.
Sweat- secreted onto skin and contains salts and fatty acids that prevent the growth of many microorganisms.
Mucus membranes- line body cavities that open to the exterior. They secrete mucus, which inhibits the entry of microorganisms to the organs of the body. The whole digestive, urinary and reproductive tracts are protected in this way. Also in ears.
Cilia- hair like projections that like tranche and brochi, that beat, moving mucus and trapping particles and microorganisms towards the throat where it may be coughed up or swallowed.
Acids- in stomach kill bacteria taken in with food or contained in mucus swallowed from the nose and windpipe, the vagina also has acid secretions that reduce growth of microorganisms. The sweat on the skin is also slightly acidic.
Lysozyme: enzyme that kill bacteria, found in tears, saliva, sweat, secretions of nose and tissue fluid,
Cerumen- earwax. Protects ear against bacteria as is slightly acidic and contains lysozyme enzymes.
Flushing of body fluids keeps areas relatively free of pathogens. Eg, Urine flow through urethra.
Hairs- found in nodal cavity and ears protect again invading microorganisms
+ protective reflexes
Define protective reflexes?
Protective reflexes: Automatic, involuntary response to a stimulus that help to protect the body from injury or from infection
Outline protective reflexesa.
Sneezing-Dust particles and noxious fumes which are likely to carrying microorganisms cause irritation. Stimulus is irritation of the walls of the nasal cavity, response is a forceful expulsion of air from the lungs which carry mucus, foreign particles and irritating gases through the nose and mouth
Coughing- Stimulus for coughing is irritation of respiratory tract (bronchi and bronchioles) resulting in air being forced from lungs to remove irritant.
- air drives mucus and foreign matter up the trachea towards the throat and mouth.
Vomiting- Vomiting has a psychological stimuli. Excessive stretching of the stomach and bacterial toxins can induce vomiting, Which is the contraction of muscles of the abdomen and diaphragm in order to expel the stomach contents.
Diarrhoea-Irritation of small and large intestines by bacteria, viruses or Protozoans can cause diarrhoea. The irritation causes increased concentrations of the muscles of the walls of the intestines so that the irritant can be removed as quickly as possible.
-Diarrhoea happens when material does not stay in large intestines long enough for water to be absorbed to the faeces are very watery
Define phagocytes?
Phagocytes- cells that are able to engulf microorganisms and cell debris
Phagocytosis?
Phagocytosis: ‘ cellular eating’
Leukocytes?
Leucocytes- a white blood cell
Define macrophages?
Macrophages- a phagocytise cell derived from a monocyte (type of white blood cell)
Define inflammation?
Inflammation- the response to damage to a tissue; involves swelling, heat, pain and redness in the affected area.
Purpose of inflammation?
Purpose of inflammation:
> reduce spread of any pathogen, to destroy the, and to prevent the entry of additional pathogens
> remove damaged tissue and cell debris
> begin repair of the damaged tissue
Outline inflammatory response?
Inflammatory response
1. Damaged mast cells in connective tissue cause release of histamine and heparin
- Histamine increases blood flow to site of injury. Vessel becomes leaky, bringing necessary components to site.
- heparin prevents blood clot to immediate area. (Clot forms around actual damaged vessels to prevent spread of infection)
- Mast cells initiate release chemicals which attract phagocytes (chemotaxis) causing phagocytosis of debris and invading pathogens
- Abnormal conditions in the tissue stimulate pain receptors, and so the person feels pain in the inflamed area
- Phagocytes filled with bacteria and debris-> die and become pus
- Mitosis-> produces new cells and repair damaged tissue
Pyrexia?
Pyrexia- body temperature above the normal range (37°c) with no known cause ( exercise/ menstural cycle not regarded as fever)
What controls fever?
Hypothalamus ( above pituitary gland)- controls body temperature thermostat set at 37°.
If cold-> goosebumps, conscious changes, vasoconstriction, shivering
If hot-> sweat, vasodilation
Outline fever process?
dangerous if too hot around 41°-> body tissue/ enzymes start to denature - convulsions (fit) + organ failure
- Pathogens enter body or cancer cells, autoimmune disease, heatstroke develop or medications cause response
- Pathogens are destroyed by leukocytes which then send a chemical message to the hypothalamus
- Thermostat is reset higher, body activity heats up to reach new temp initially person feels cold ( shivering and vasoconstriction) when body reaches temp person feels hot ( sweating and vasodilation)
- If pathogen removed thermostat resets to normal 37° and body cools down
- Of pathogen not removed, thermostat resets higher and process repeats itself
How does increasing body temperature affect your body?
Increasing body temperature:
Denatures and inactivates pathogens
Increases leukocyte activity so faster destruction and phagocytosis of pathogens
Increases rates of repair of damaged tissues#
What are antibiotics and what type of pathogens do they target?
Antibiotics: a chemical able to inhibit the growth of, or kill, microorganisms, particularly bacteria
What type of pathogen: they fight infections of microorganisms, particularly bacteria (sometimes fungi)
2 types of antibiotics?
bactericidal antibiotics- kill bacteria by changing the structure of the cell wall or cell membrane ( cell wall synthesis) by disrupting the action of essential enzymes,
Bacteriostatic antibiotics - rather than killing they stop bacteria from reproducing and inhibit growth, usually ( altering shape of ribosomes/ tRNA) by disrupting protein synthesis, preventing metabolic processes ( ie. cell respiration, altering nucleic acid/ preventing respiration
What are antivirals and what pathogens do they target?
Antivirals: a drug user for the treatment of viral infections
What type of pathogens?: viral infections
Antivirals mode of action and examples?
Mode of action:
Inhibit the development of viruses (inactivates) viral proteins are disabled by specifically designed chemical. They prevent viruses from entering cell, synthesis of virus genome, prevent synthesis of viral proteins and prevent release of virus.
Examples:
Acyclovir- herpes infections
Interferons- hepatitis B
How are they made?
…
What are the functions of the lymphatic system and roaming macrophages?
- Collect fluid lost by capillaries and returns it to the bloodstream
- Absorb fatty acids and glycerol in the small intestines
- Contains leukocytes which destroy and remove pathogens
Characteristics of lymph nodes
- numerous in neck, armpit and groin
- bean shaped
- 1-25 mm diameters
- encapsulated in connective tissue
contain macrophages
Characteristics of macrophages?
- large phagocytes
- roam in lymph targeting foreign bodies (non cell antigens)
phagocytosis takes pathogen into the cell and digests
Role of third line of defence
Guard against SPECIFIC types of antigens by initiating a response by specific leukocytes. B and T lymphocytes are programmed to recognise antigens on pathogens and are activated to initiate an immune response
Where do b and t t lymphocytes originate
Bcells : originate and mature in bone marrow
Tcells: orgininate in bone marrow and mature in thymus gland
Mode of action for b and t lymphocytes
B: chemical -> produce antibodies
T: cellular-> types of T cells with various roles
What cells are involved In antibody mediated response
B plasma cell- produce antibodies
B memory cell
Target of antibody mediated response
Extra cellular bacteria/ virus
Try to remove before cell in affected
Target of cell mediated response
Intracellular phase of infections to destroy affected cell , cancer, foreign tissues ( eg. Transplants) and larger particles
Longevity of b and T cells
B: relatively short lived ( b plasma cells)
T: relatively long lived
In humoral response, how do SPECIFIC B cells know what antigens on pathogens to target?
There are receptors on the B cells
What happens in the humoral response when a B cell is activated?
Growth and proliferation (cloning)
What group of proteins are antibodies a part of?
Immunoglobulins
What happens when antibodies meet with antigens?
- they inactivate the pathogen
- immobilise
- dissolve pathogen
- agglutination ( cause antigens to clump together)
- coat pathogen-> attract phagocytes
neutralise bacterial toxins or viruses by coating them and preventing them entering cells
Define T cells?
T cells- Lymphocytes that mature in the thymus gland containing receptors for specific antigens. They work against intracellular phase of infection to destroy affected cells, cancer cells and foreign tissue transplants.
Types of antigen presenting cells involved in cell mediated response?
Macrophages, B cells, helper T cells etc. come in contact with a specific T cell which is activated and then divides
What types of cells do T cells divide into?
Cytotoxic T cells, helper T cells, suppressor T cells and memory T cells
Role of cytotoxic/ killer T Cells
Cytotoxic T cells- Killer T cells that secrete a chemical which dissolves the pathogen or cause it to burst (lose)
Difference between primary and secondary immune response?
The primary response is the response to the initial exposure to the antigen. It takes more time for antibodies to be developed because of this and there symptoms are worse.
The secondary response is the response to the second or any subsequent responses after the initial. It takes less time for antibodies to develop as the body already contains memory cells. Because of this the symptoms are often less severe or they are no symptoms
What are the four types of immunity + examples?
Natural passive: immediate, temporary immunity with no human intervention. When pathogens are passed from 1 person to another
( mother to foetus across placenta and amniotic fluid)
Natural active: takes time and is prolonged immunity with nohuman intervention. When Natural exposure to antigens occurs. ( chicken pox, flu virus)
Artificial passive:immediate, temporary immunity with human intervention. When antibodies are injected into the blood stream. ( serious illness where immediate action is required eg, tetanus, diphtheria or if someone has a poor immune system )
Artificial active:takes time and is prolonged immunity with human intervention. Occurs when antigen injected into the body initiates an immune response to produce antibodies. ( vaccines, eg. Measles, mumps) it is preventative
Immunisation? + reasons for and against
Programming the immune system so that the body can respond rapidly to infecting microorganisms
Reasons for immunisation:
all tested rigorously by by law in AUS
herd immunity
Objections to immunisation:
some contain chemicals that are poisons such as mercury ( as a preservative)
May contain allergens
Religious objections
Vaccination, vaccine?
Vaccination: The introducing of antigens to a person so that they Aquire immunity without suffering from the illness
Vaccine: An antigen preparation used in immunisation
What are the 4 types of vaccines + examples of each type?
- living attenuated microorganisms eg. Measles, mumps and rubella ( reduce ability to produce disease symptoms)
- dead microorganisms eg. Cholera, bubonic plague ( immunity not as prolonged as first type)
- toxoids eg. Diphtheria, tetanus. ( made from filaments of bacterial cultures containing toxins- toxins are inactivated)
subunit eg. Human papilloma virus, hepatitis b. ( fragment of organism is used to provoke immune response )
Herd immunity?
Herd immunity: Type of group immunity that occurs when a high proportion of people in a population are immunised that those who are not immunised are protected
Alzheimer’s + causes and effects + treatment
Alzheimer’s: form of dementia causing problems with memory thinking and behaviour
Cause:
People with Alzheimer’s disease have abnormal clumps (amyloid plaques) & tangled bundles of fibres (tau tangles) in the brain. Symptoms
Effect:
Alzheimer’s disease is characterised by progressive & irreversible mental deterioration. It gradually destroys memory & thinking skills, eventually leading to confusion, mood swings, aggression & general withdrawal.
Treatment: Treatment Drugs are available to manage the symptoms of the illness & slow its progress. Drugs aim at increasing acetylcholine levels, as acetylcholine is a neurotransmitter essential for processing memory & learning.
Parkinson + causes, effect and treatment?
Cause:
Destruction of dopamine-producing cells in the basal nuclei of the cerebrum.
Symptoms:
Slowed physical & mental responses, muscular tremors, stiffness of the limbs, impaired balance & coordination.
Treatment:
A variety of medications which either contain or act like dopamine, block acetylcholine or prevent the breakdown of dopamine.
2 types of glands
Exocrine and endocrine
Endocrine glands: Glands that secrete hormones isn’t extracellular fluid that surrounds the cells that make up the gland. The secretion usually passes into the capillaries to be transported by the blood. Endocrine glands are ductless.
Exocrine glands: Glands that secrete hormones into a duct that carries the secretion to the body surface of to one of the body cavities
Endocrine vs exocrine glands examples?
Exocrine gland examples Sweat glands Salivary glands Sebaceous glands Glands of the alimentary canal
9 major endocrine glands Pineal Hypothalamus Pituitary Thyroid Parathyroid Thymus Adrenal Pancreas Gonads
Endocrine hormones of pituitary gland
Endocrine hormones of pituitary gland Follicle stimulating hormone Luteinising hormone Growth hormone Thyroid stimulating hormone Adrenocorticotropic hormones? Prolactin Antidiuretic hormone Oxytocin
Hormones produced by posterior lobe of pituitary gland
Oxytocin and antidiuretic hormone
Hormones released by thyroid
Thyroxine which targets most body cells to increase metabolic rate and thence oxygen consumption and heat production
Hormones released by parathyroid
Parathyroid hormone which targets the bones and kidneys to increase rate of osteoclast activity, increasing levels of calcium in blood and control phosphate levels
Target of follicle stimulating hormone
The gonads where it stimulates growth of follicles and the production of spermatogonia
Lutenising hormone target
- Ovaries in females where it is involved in ovulation and maintainance of corpus luteum.
- leydig cells in the testes of males where it stimulates secretion of testosterone
Growth hormone target
Growth hormone target
All cells, stimulating growth and protein synthesis
TSH target
TSH target
Thyroid stimulating production of hormones of thyroid gland
Adrenocorticotropic hormone target
Adrenocorticotropic hormone
The adrenal cortex where it stimulates secretion of hormones from the adrenal cortex
Prolactin hormone target
Prolactin hormone target
The mammary glands where it stimulates production of milk
Anti diuretic hormone target
ADH target The kidneys ( specifically the distal proximal tubule and collecting duct of nephrons) where it causes reabsorption of water
Oxytocin target
Oxytocin target
The uterus where it allows contractions during childbirth and
The mammary glands which allow the release of milk
Where is thymosins released and what is its effect?
It is released by the thymus and targets t lymphocytes to stimulate development and maturation of T lymphocytes
Where is aldosterone released and what is its effect?
Released by the adrenal cortex to target the kidney/ nephron ( WHERE SPECIFICALLY) where it increases reabsorbtion of sodium ions and secretion of water and potassium ions
Hormones released by adrenal cortex
Hormones released by adrenal cortex
Aldosterone and cortisol
Where is cortisol released and what is its effect?
Where is cortisol released and what is its effect?
The adrenal cortex to target most cells where it promotes normal metabolism; helps the body deal with stress and promotes repair of damaged tissues
Hormones produced by adrenal medulla
Adrenaline and noradrenaline
Where is adrenaline and noradrenaline released and what are their effects?
Produced by the adrenal medulla and targets most tissues where it prepares the body for fight or flight response ; reinforcing the effects of the sympathetic nervous system
Where is insulin released and what is its effect?
The pancreas to target most cells where it stimulates uptake of glucose; lowers blood glucose level
Where is glucagon released and what does it target?
Released by the pancreas and targets the liver and fat storage tissues to stimulate breakdown of Glycogen and fat; increase blood glucose levels
Where is Androgens (testosterone) released and what does it target?
In the testes where it targets many tissues to stimulate sperm production, growth of skeleton and muscles; male sexual characteristics
Where is ostrogen released and what does it target?.
Released by the ovaries, targeting many tissues to stimulate development of female secondary sexual characteristics and regulate menstrual cycle and development of endometrium
Where is progesterone released and what does it target?
Released via the ovaries to target
..the uterus where it regulates menstrual cycle and pregnancy and maintains endometrium
..the mammary glands where it prepares the mammary glands for milk secretion
Where is the hormone calcitonin produced and target once released?
Produced by the thyroid to target bones kidneys and intestines where it is involved in calcium regulation
How do proteins and amine hormones send chemical messages?
Proteins and amines are water soluble so they can’t enter, instead Hormone attaches to protein specific receptor in the membrane of the target cell. The combo of hormone with the receptor causes a secondary messenger substance to diffuse through the cell and activate Particular enzyme.
How do steroid hormones send chemical messages?
Steroid hormones are lipid soluable so they enter the target cell and combine to a receptor protein inside the cell. The receptor may be mitochondria, on other organelles of in the nucleus. The hormone receptor complex activates the genes controlling formation of particular proteins
What type/s of hormones can and can’t enter the cell?
Steroids can because Cell membrane is made of a phospholipid bylayer. Steroid hormones are lipid soluable so they enter the target cell and combine to a receptor protein inside the cell.
Protiens and amines can’t.Proteins and amines are water soluble so they can’t enter, instead Hormone attaches to protein specific receptor in the membrane of the target cell
What are the 2 lobes of the pituitary gland, how are they different?
Anterior lobe - releases and produces hormones. hormone secretions are controlled by regulating factors. Hormones are secreted into EF surrounding the cells of hypothalamus and carried by blood to Anterior lobe.
Posterior lobe- doesn’t produce hormones but releases them. Joined to hypothalamus by the nerve fibres that come from nerve cell bodies in hypothalamus and pass through the infundibulum to the posterior lobe.
Lipid and water soluble hormones examples
Lipid soluble hormones- cortisol, aldosterone
Water soluble hormones- FSH, insulin,
Relationship between hypothalamus and pituitary gland? (Posterior lobe)
Posterior lobe-
+ not a true gland as doesn’t produce hormones. hormones are produced by neurosecretory neurons
+produced in the soma, travel down axon and are stored in the axon terminals in the posterior lobe.
+ nerve impulse triggers the release of hormones from axon terminals in the posterior lobe where they are stored until a nerve impulse initiates release and hormones are releases into bloodstream.
(Antidiuretic hormone and oxytocin)
Relationship between hypothalamus and pituitary gland? (Anterior lobe)
+Hypothalamus produces releasing and inhibiting factors in neurosecretory neurons.
+factor is secreted into hypophyseal portal system and bloodstream carries factors directly into the anterior lobe
+ factors reach target endocrine cells (with corresponding receptors) and initiate a response:
Releasing factor would increase production/ release of hormone. Inhibiting factor would decrease production/ release of hormone.
(Eg, growth hormone inhibiting and releasing factor)
hormones released travel through extracellular fluid and into the bloodstream, travelling around it until it reaches its target cells.
Infundibulum?
Infundibulum is the sack like structure that joins the pituitary gland to the hypothalamus
BMR or basal metabolic rate?
is the sum total of all the body’s reactions when at rest. It is the measure of the amount of energy the body uses when at rest.
Why is regulation of calcium essential?
Essential for nerve impulse contraction and bone strength. It is controlled by calcitonin, vitamin D and parathormone
What happens if blood calcium levels are low?
Stimulus: low blood calcium levels
Receptor: chemoreceptors in parathyroid gland
Modulator: parathyroid gland which releases parathormone
Effector:bones, kidneys, intestines
Response:
bones- osteoclast break down bone for calcium
kidneys- reabsorption of calcium
Intestines- absorption of calcium increase
Feedback: increased calcium in bloodstream (negative)
What happens if blood calcium levels are too High?
Stimulus: high blood calcium levels
Receptor: chemoreceptors in parathyroid gland
Modulator: thyroid which releases calcitonin
Effector:bones, kidneys, intestines
Response:
bones- osteoblasts build up bone for calcium
kidneys- decreased reabsorption of calcium
Intestines- decreased absorption of calcium increase
Feedback: decreased calcium in bloodstream ( negative)
What happens if thyroxine levels in blood are too high
Stimulus: high levels of thyroxine in blood
Receptor: chemoreceptors in hypothalamus
Modulator: hypothalamus produces thyroid stimulating hormone inhibiting factor which stimulates the anterior lobe of PG to decrease TSH production and release.
Effector: thyroid gland
Response:thyroid produceses less thyroxine
Feedback, decreased levelsof thyroxine in bloodstream ( negative)
What happens if thyroxine levels are too low
Stimulus: low levels of thyroxine in blood
Receptor: chemoreceptors in hypothalamus
Modulator: hypothalamus produces thyroid stimulating hormone inhibiting factor which stimulates the anterior lobe of PG to decrease TSH production and release.
Effector: thyroid gland
Response:thyroid produceses less thyroxine
Feedback, decreased levelsof thyroxine in bloodstream
What happens if there is high metabolism/ increased body temperature
Stimulus: increased metabolism/ body temperature
Receptor: thermoreceptors in the skin and hypothalamus as well as chemoreceptors in hypothalamus detect thyroxine levels
Modulator: hypothalamus releases thyroid stimulating hormone inhibiting factor which decreases TSH production in Anterior lobe of pituitary gland affecting the thyroid gland to produce less thyroxine
Effector: somatic cells
Response: decreased metabolism causes decreased protein synthesis and cell respiration
Feedback: reduced metabolism and reduced body temperature (negative)
What happens if there is low metabolism/ decreased body temperature
Stimulus: decreased metabolism/ body temperature
Receptor: thermoreceptors in the skin and hypothalamus as well as chemoreceptors in hypothalamus detect thyroxine levels
Modulator: hypothalamus releases thyroid stimulating hormone releasing factor which increases TSH production in Anterior lobe of pituitary gland affecting the thyroid gland to produce more thyroxine
Effector: somatic cells
Response: increased metabolism causes increased protein synthesis and cell respiration
Feedback: increased metabolism and increased body temperature (negatiVe)
Causes, effect and treatment of Hyperthyroidism
Hyperthyroidism: Overproduction of thyroxine
Eg. Graves’ disease: most common type
Cause: caused by an immune system reaction and there seems to be genetic predisposition for the condition
Effect: increased rate of metabolism, nervousness, anxiety, weight loss, rapid heart rate, hand tremors, sleeping problems, excessive sweating, feeling hot.
Treatment:
- drugs that blocks thyroid glands use of iodine
- surgery to remove some of or all of gland
- drink containing radioactive iodine molecules which are taken up by thyroid cells wh
Causes, effect and treatment of hypothyroidism
Hypothyroidism: underproduction of thyroxine
Eg. Hashimotos: deficiency caused by attack on the thyroid gland by patients immune system
Cause: problems which thyroid gland or pituitary gland or hypothalamus, lack or iodine in diet, surgery removing gland
Effect: weakness, fatigue, weight gain or difficultly regulating weight, intolerance to cold, muscle cramps, depression slowing of mental capabilities, rough or dry skin, deepening voice, memory loss, swollen younger and face, goitre
Treatment:
inclusion of extra iodine in diet
thyroxine tablets
no cure and hormone tablets must be taken for rest of life
What happens if there is an autoimmune attack on the thyroid causing over production of thyroxine.
Stimulus: high levels of thyroxine in blood
Receptor: chemoreceptors in hypothalamus
Modulator: hypothalamus produces TSHIF cause my decreased production and release of TSH in pituitary gland
Effector: autoimmune response leads to increase in size of thyroid
Response: thyroid continues to produce thyroxine despite no TSH available
Feedback: thyroxine remains high in blood ( positive)
What happens if there is a lack of iodine in diet due to an autoimmune response destroys that thyroid cells or surgery?
Stimulus: low levels of thyroxine
Receptor: chemoreceptors in hypothalamus detect
Modulator: hypothalamus releases TSHRF to pituitary gland causing increase TSH
Effector: thyroid gland is for whatever reason not able to respond
Response: no thyroxine produced
Feedback: low levels of thyroxine (positive)
Thermoregulation ?
Thermoregulation: The regulation of body temperature, the balance of heat gain and heat loss in order to maintain a constant internal body temperature independent of environmental temperature
Body responses to hot and cold
If body temperature is too hot:
- Vasodilation: radiation and convection
- Sweating: evaporation allows increased heat loss
- long term they can be an decrease in metabolic rate= heat loss
- behavioural response
If body temperature is too cold
vasoconstriction decreases blood flow to skin
adrenal medulla stimulated to secret adrenaline and noradrenaline
shivering increases friction and cell respiration
increased thyroxine production/ metabolism
behavioural response
How is low body temperature regulated through behavioural response?
S: Low temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus
E: cerebral cortex
R: conscious changes
F: increased body temp
How is low body temperature regulated through shivering?
S: Low temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus sends nerve impulse to cerebral cortex
E: primary motor area in frontal lobe
R: rhythmic contracting and relaxing causing increased cell respiration and friction
F: increased body temp
How is low body temperature regulated through vasoconstriction?
S: Low temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus sends nerve impulse to medulla which sends message to…
E: skin blood vessels
R: prevents blood going to skin= less heat lost
F: increased body temp
How is low body temperature regulated through increasing metabolism?
S: Low temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus
E: somatic cells
R: more thyroxine production increased respiration
F: increased body temp
How is low body temperature regulated through secreting adrenaline and noradrenaline ?
S: Low temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus sends nerve impulse to medulla olongata via Autonomic nervous system sympathetic route.
E: adrenal medulla
R: release noradrenaline to increase cell respiration and heat production
F: increased body temp
How is high body temperature regulated through behavioural response?
S: high temperature
R: heat thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus
E: cerebral cortex
R: conscious changes
F: decreased body temp
How is high body temperature regulated through sweating
S: high temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory centre of hypothalamus sends nerve impulse via Autonomic nervous system
E: sweat glands
R: produce and release sweat which then evaporates
F: decreased body temp
How is high body temperature regulated through vasodilation ?
S: high temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory centre of hypothalamus sends nerve impulse to medulla which sends Autonomic impulse to vessels
E: smooth muscles in arterialise going to skin
R: blood vessels vasodilation increasing blood flow to skin allowing radiation and convection
F: decreased body temp
How is high body temperature regulated through decreasing metabolism ?
S: high temperature
R: thermoreceptor in skin and hypothalamus
M: heat production centre of thermoregulatory center of hypothalamus
E: somatic cells
R: decreased metabolism= less heat production
F: decreased body temp
Heat transfer?
Heat transfer: Balancing the loss and gain of heat through transferring it.
Heat transfer types
Types of heat transfer: Conduction Convection Radiation Evaporation
Outline heat transfer methods
Conduction: -When heat energy moves FROM A WARMER OBJECT TO A COOLER OBJECT when they are in DIRECT PHYSICAL CONTACT
- if you touch a cold object passes from your body to the object and reverse happens when you touch something hotter than ur body
Convention: - An object will HEAT OR COOL AIR as it passes over the object
the CURRENTS OV MOVING AIR REMOVE HEAT ENERGY from the object
Radiation: - heat energy moves FROM A WARMER OBJECT ACROSS A SPACE
- no contact necessary
- if your body has higher temp than the environment you will radiate heat into environment which cools the body and visevera
Evaporation:- LIQUID water is CONVERTED to WATER VAPOR
- REQUIRES ENERGY (in the form of heat) which is taken from body-> body cools
as we sweat the evaporation of sweat from the skin cools the body
How is heat produced
How is heat produced?
Carbohydrates, proteins and lipids we eat contain energy and in the process of cellular respiration food is oxidized in cells and energy released. Whilst some energy is used for cellular and body activity, most is released in form of heat
Define metabolic rate
Metabolic rate: Rate at which energy is released by the breakdown of food.
Exercise, stress and body temperature all affect this
Types of thermoreceptors
Types of thermoreceptors: Peripheral and centeral
Central- hypothalamus
Peripheral- skin and some mucous membrane
Types of peripheral thermoreceptors?
Cold and heat receptors
# temperature above Above 45° is lethal #
Define heatstroke
Heatstroke: When body temperature continues to rise and regulatory Mechanisms cease and body cannot lose heat by radiation or evaporation( often due to humidity and high body temp)
Cured by quickly cooling body in cold water
Define heat exhaustion
Heat exhaustion: Loss of water reduces volume of blood plasma lowering blood pressure and output causing person to maybe collapse.
Often occurs as a result of extreme sweating and vasodilation
What is the optimum temperature for cellular respiration
37° is optimum for cellular respiration #
heat gain must be equal to heat loss, true or false..
True
High blood glucose can be an indication of ….
High blood sugar= can lead to diabetes
What is diabetes caused by?
Caused by not enough insulin to manage glucose levels or; when insulin is not effective enough because your body is ‘insensitive’ to insulin
What does glucagon do?
Increase glucose levels
Where does insulin come from?
Secreted by beta cells in islets of langerhan in pancreas gland
Where does glucagon come from?
Alpha cells In islets of langerhan in the pancreas
Blood glucose regulation feedback loop for low blood glucose
S= low blood glucose levels
R= pancreas has islets of langerhan alpha cells have chemoreceptors on them
M= alpha cells in pancreas secrete glucagon
E= liver, adipose tissue, cells
R= gluconeogenesis, lypolysis, glycogenlysis
F= increased blood glucose
(Negative feedback loop)
Lypogenesis
Lypogenesis: Metabolic formation of fat
-Happens to adipose tissue
(Decreases BG levels)
Gluconeogenesis:?
Making glucose from protein
-Happens to all cells
(Decreases BG levels)
Lipolysis?
Breakdown of fats and other lipids by hydrolysis to release fatty acids which converts into glucose
- adipose tissue
(Increases BG levels)
Translocation?
Movement of glucose from blood stream into cells
Happens at all cells (Decreases BG levels)
Protein synthesis role in glucose regulation?
Stimulated by the release of insulin and acts to reduce blood glucose levels
-Happens at all cells
(Decreases BG levels)
Glycogenolysis?
Glycogenolysis: Process of converting glycogen back to glucose
(Increases BG levels)
Glycogenesis?
is the process of glycogen synthesis, in which glucose molecules are added to chains of glycogen for storage.
(Decreases BG levels)
What responses occur to reduce blood glucose?
-translocation
-lipogenesis
- protein synthesis
glycogenesis
