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38 Cards in this Set
- Front
- Back
Bones (7 points) |
• the job of the skeleton is to support the body and protect vital organs • internal skeletons easily grow with the body, can attach muscles, more flexible and provide more framework
• long bones like in the thigh are hollow which makes them lighter and stronger than solid bones of the same mass • the hole in the middle is filled with bone marrow that makes new blood cells • the top of the bone contains cartilage to stop it rubbing and to act as a shock absorber
• bone starts as cartilage; as we grow calcium and phosphorous are deposited on this turning it to bone. called ossification • do to tell someone's age look at their amount of cartilage |
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Bone and Cartilage Damage (5 points) |
• they're made of living tissue, so can repair themselves but can also get infected • they can be fractured or broken • old people can contract osteoporosis - where calcium is lost from the bones. bones become brittle and weak • as we get older bones become more porous and weaker • broken bones can damage nearby tissue. if someone has. spinal fracture they shouldn't be moved because they could damage the CNS and become paralysed |
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Joints: (5 points) |
Synovial: • bones at these joints held together by ligaments (high tensile strength, elastic) • ends of bones have cartilage; stops rubbing, shock absorber • synovial membrane releases synovial fluid that lubricates the joints
Other Joints: • ball and socket joints (hips, shoulder) can move and rotate in all directions • hinge joints (knee, elbow) can only move backwards and forwards |
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Muscles and Joints (4 points) |
• muscles are attached to the bone by tendons • they can only move bones by contracting i.e. they can't push bones, only pull • they work in antagonistic pairs (when one contracts the other relaxes) to move the bone • the bicep and triceps muscles act as antagonistic pairs and move the arm using the elbow as a pivot, or fulcrum |
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Circulatory Systems (5 points) |
• all multicellular organisms require circulatory systems; diffusion in them is too slow and they need a method to transport materials
• fish have a single circulatory system, a two chambered heart to pump out blood and receive it from the rest of the body
• humans have a double circulatory system with a four chambered heart to pump blood to the body and lungs and then receive it • allows us to pump our blood around faster, means materials are transported faster, more respiration, more energy to maintain temp.
• unborn babies don't need a double circulatory system because they get oxygen from the placenta; they have a hole in their heart until they're born |
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Cardiac Cycle (4 steps) |
1. atrio-ventricular valves open and blood flows into atria and ventricles
2. SAN causes atria to contract pushing blood into ventricles through atrio-ventricular valves.
3. AVN causes ventricles pushing blood out of open semilunar valves and aorta, pulmonary artery. atrio-ventricular valves automatically close to prevent backflow
4. blood flows along arteries and the cycle begins again |
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Theories on the Heart (6 points) |
Galen: • Greek. Dissected animals to study the heart • thought arterial blood was made by heart whilst vein blood made by liver, sucked through blood and consumed by organs
Harvey: • showed that: valves stopped backflow of blood • heart is a pump • pulse is caused by heart pumping • same blood circulated, not consumed |
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Heart Rate and Pacemakers (7 points) |
• when we exercise carbon dioxide produced and brain detects this so heart rate rises to remove it • hormones like adrenaline can raise heart rate to deliver oxygen for when we need it (i.e. when in danger)
Pacemakers: • cells that cause the heart to beat • SAN makes atria contract, AVN makes the ventricles • the SAN makes an electrical impulse to make the atria contract, which stimulates the AVN to make an electrical impulse and the ventricles contract • this means the atria always contract first • artificial pacemaker can treat a heart that doesn't work properly. a wire goes in to the heart and produces an electrical signal |
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Electrocardiograms and Echocardiograms (6 points) |
ECGs: • can show if you're having a heart attack • irregular heartbeats and general heart health
Echocardiograms: • ultrasound scans • show an enlarged heart (indicative of heart failure) • decreased pumping ability • valve function; if they torn/infected |
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Heart Disease (12 points) |
Hole in the Heart: • gap in the wall between ventricles or atria • allows deoxygenated and oxygenated blood to mix, less oxygen delivered to body cells • corrected by surgery
Valve Damage: • causes by heart attack, infection, old age • may not open properly allowing blood to flow in both directions, high blood pressure, blood doesn't circulate effectively • corrected by artificial valve replacement
Coronary Heart Disease: • coronary arteries supplying the heart get blocked by fatty deposits • blood to heart restricted and risk of heart attack • corrected by (coronary bypass) another vein being inserted to bypass the blockage
Other Surgery: • heart transplant • heart assist device which takes over the role of heart • new bits like valves, pacemakers |
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Artificial Replacements (3 points) |
• main advantage is no chance of rejection as parts are dead material with no antigens • much less drastic with lower recovery times • however will not last long and require replacing |
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Platelets and Clotting (5 points) |
• when we're injured, platelets in the blood cause chemical reactions that make a clot (a mesh of fibrin fibres) that plugs the damaged area • too little clotting means we could bleed to death • too much means we get get strokes and thrombosis • warfarin, heparin and aspirin reduce clotting • haemophilia means the blood can't clot because a clotting agent is missing, which can be injected to treat it |
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Blood Types and Agglutination (4 points) |
• people are either A, B, AB or O blood group. Refers to the type of antigens on the red blood cells • blood plasma has antibodies • if an anti-A antibody for example, meets an A antigen they clump together; called agglutination and is bad because it can cause blood clots • antibodies are agglutinins |
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Organ Donation (8 points) |
• living donors can donate things like a kidney or a piece of liver • organs of those recently dead can be transplanted
Requirements: • young so the organ is fit and healthy • similar body weight and type so the organ fits • close tissue match so no rejection • living donors must be over 18 • dead donors' family must give permission • dead donors must have died very recently |
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Problems With Organ Transplants (9 points) |
Medical: • the immune system may recognise the new organ as foreign and attack it • the donor needs a similar tissue type (similar antigens) to the patient • doctors use immuno-suppressive drugs but this can leave patients vulnerable to infection
Ethical: • some people believe life and death is up to God • others worry doctors won't save them if they're critically ill to harvest their organs • worries that living donors will be pressured into it
Supply: • we have a shortage of organs because we have an 'opt-in' system and family need to give permission; they're often grieving • patients therefore have to wait a long time and could die waiting • one solution would be an 'opt-out' system where we assume it's ok to take the organs unless they register not to |
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Mechanical Replacements (7 points) |
• heart-lung machines - keep blood oxygenated and pumping • kidney dialysis - filters a patient's blood • mechanical ventilators - push air in and out of a patient's lungs if they stop breathing
Problems: • need constant power supply • large and difficult to move • cause inflammation or allergic reactions • must be made of materials that won't harm the body |
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Inspiration and Expiration (4 points) |
Inspiration: • intercostal muscles and diaphragm contract and increase the volume of the thorax • pressure in the lungs decreases and air rushes in
Expiration: • intercostal muscles and diaphragm relaxes; thorax volume decreases • higher pressure in lungs pushes air out |
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Role of the Kidneys (4 points) |
• removal of urea made in the liver from excess amino acids • adjustments of salt levels • adjustment of water content • they filter out nasty stuff and reabsorb good stuff. urine is made. |
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Blood in the Kidneys (8 points) |
Ultrafiltration: • high pressure blood squeezes water, urea, salts and glucose out of the glomerulus (network of capillaries, good supply) and into Bowman's capsule • membrane acts as filter so proteins and blood cells don't leave - too big
Reabsorption: • some things are selectively transformed along the nephron • all sugars are absorbed by active transport (body needs glucose for respiration) • sufficient salt is absorbed by active transport. excess salt is left behind • sufficient water is reabsorbed according to ADH levels
Waste Release: • urea, excess salt, excess water not reabsorbed • continue out of nephron, into collecting tube, through ureter into bladder then out the urethra as urine |
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Spirometers (3 points) |
• total volume of air you can fit in your lungs is your total lung capacity • normal volume of air you breathe is your tidal air • the air left behind so the lungs don't collapse is your residual air • total lung capacity minus residual air gives vital capacity air - maximum amount that can be breathed in/out |
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Human Gaseous Exchange (8 points) |
• blood passing by the alveoli has lots of carbon dioxide and little oxygen • carbon dioxide diffuses into alveoli and out of red blood cells; oxygen diffuses out of alveoli and into red blood cells • the red blood cells are then pumped around body, oxygen diffuses into body cells and carbon dioxide into the red. mood cells
Alveoli: • very large surface area • moist surface so CO2 and O2 dissolves, faster • permeable surface • one cell thick • good blood supply (steep concentration gradient) |
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Gaseous Exchange in Fish and Amphibians (6 points) |
Amphibians: • have simple lungs • permeable and moist skin to allow diffusion in and out • however, skin is now not waterproof so amphibians must live in a moist environment or have a layer of slime if they live in a dry one
Fish: • gaseous exchange occurs in gills at the side of the head • fish opens mouth, water rushes in, when closed water is pushed over gill filaments and oxygen in water disused into blood vessels • water keeps gill filaments separated; if no water they stick together and the fish suffocates |
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Cilia and Mucus (3 points) |
• cilia and mucus secreting cells line the trachea and bronchi • mucus traps small particles and pathogens, cilia brush it to back of throats where stomach acid kills them • if cilia damaged then lungs very prone to infection as lungs are a dead end |
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Lung Diseases (4 points) |
• bronchitis - virus or bacteria maybe smoking, coughing bringing up yellow mucus, sore throats, wheezing and blocked nose • asbestosis - caused by asbestos fibres trapped in alveoli, inflammation and scarring of alveoli, difficulty in breathing and gaseous exchange maybe cancer • cystic fibrosis - genetic, cells lining the trachea and bronchi produce very thick mucus and cilia aren't hydrated enough to waft away. chest infections, lung damage • lung cancer - smoking, cells dividing out of control, reduced gaseous exchange, chest pain, coughing w blood |
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Asthma (5 points) |
• caused by inhaling pollen or allergens, infection, cold air and stress • asthmatic's lungs are overly sensitive to dust etc, when they encounter them muscles around bronchioles contract and construct airways • lining of airways becomes inflamed and fluid builds up • they have an asthma attack: difficulty breathing, wheezing, tight chest • when symptoms appear a muscle relaxant drug is inhaled |
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Causes of Lung Disease (3 points) |
• industrial materials - like asbestos causes asbestosis • genetics - cystic fibrosis is an inherited condition • lifestyle - tar from smoking causes lung cancer |
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Digestive Enzymes (4 points) |
• carbohydrases - break down starch first into maltose and then glucose • proteases - break down proteins into amino acids • lipases - break down fats into fatty acids and glycerol
> the end goal is to break large insoluble molecules into smaller soluble ones that can be absorbed into blood plasma/lymph |
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Digestion (7 steps) |
1. mechanical digestion in mouth increases surface area, carbohydrases present here
2. swallow them. churning in stomach increases surface area, pH of about 1-2 optimal for proteases to work
3. enters duodenum where bile from the liver emulsifies fat into smaller droplets (bigger SA). bile is alkaline and neutralises acid to make right conditions for small intestine; pancreas adds lipase, protease and carbohydrase
4. enters small intestine, which is very long with a huge SA (villi and microvilli), permeable, one cell thick, good blood supply, fast diffusion
5. glucose and amino acids enter the blood plasma but fat products go into lymph, then emptied into blood
6. waste products stored in rectum
7. waste products expelled out of anus in egestion |
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ADH and Water Content (6 points) |
• amount of water reabsorbed controlled by ADH released from pituitary gland • if too much water ADH is released less and the nephron becomes less permeable so less water is reabsorbed • if too little more ADH is released so nephron becomes more permeable and more water is reabsorbed
Urine: • heat - when hotter urine becomes more concentrated as more reabsorbed • exercise - do more, more concentrated urine • water intake - if high, more dilute urine |
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Kidney Dialysis (3 points) |
• has to be done regularly to remove waste and keep dissolved substances at right concentrations • dialysis fluid has same conc. of sodium and glucose as blood so these aren't removed • has a selectively permeable membrane to let waste products through but keeps proteins etc in the blood |
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Stages of Menstruation (4 points) |
• Day 1 - uterus lining breaks down for 4 days • Day 4-14 - uterus lining builds up again into a thick spongy layer • Day 14 - an egg is released • Day 14-28 - wall is maintained for 14 days, if egg not fertilised it breaks down |
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Hormones in Menstruation (3 points each) |
FSH: • made in pituitary gland • causes an egg to develop in the ovaries • stimulates production of oestrogen
Oestrogen: • made in ovaries • causes uterus lining to repair • stimulates LH, inhibits FSH
LH: • made in pituitary gland • stimulates release of egg at day 14 • stimulus progesterone (indirectly)
Progesterone: • made in the ovaries • maintains the lining of the uterus. when levels fall the wall breaks down • inhibits LH production |
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Reducing Fertility (1 point) |
• 'the pill' contains oestrogen which inhibits the release of FSH (which triggers egg development, so egg cells never develop) |
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Infertility Treatment (4 points) |
• Artificial Insemination - man's sperm placed into a woman's uterus without sex - if sperm defects or man has infertility • FSH Injections - some women have low levels so eggs don't develop • IVF - woman's eggs are fertilised outside of the body then implanted into woman's uterus. donated sperm/eggs can be used or a surrogate mother if the mother always miscarries • Ovary Transplant - transplant a healthy ovary into the woman |
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Arguments Against Fertility Treatment (2 points) |
• throwing away extra fertilised eggs i.e. extra lives is wrong • IVF increases chances of multiple pregnancies which poses physical threats to mother's health |
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Foetus Scanning (3 points) |
• amniocentesis - long needle extracts amniotic fluid to test chromosomes to see if the baby has down's syndrome etc • however can increase risk of miscarriage • and if the baby does have a genetic defect the parents must decide if it is morally correct to abort the baby or keep it |
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Influences on Growth (4 points) |
Diet: • a poor diet lacking in proteins inhibits the growth of children
Exercise: • exercise builds muscle mass and stimulates the release of growth hormone from the pituitary gland
Genetics: • gigantism caused by a tumour on the pituitary gland meaning it released too much growth hormone • dwarfism is a genetic disease that results in stunted bone growth |
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Baby's Growth and Life Expectanty (8 points) |
• babies grow at different rates; the head grows very quickly • the length, mass and head size of baby is plotted on average growth charts • of the baby falls above the 98th percentile or below the 2nd percentile this is cause for concern and can indicate water on the brain, malnutrition, dwarfism
Life Expectancy: • medical advancement • healthier diet and lifestyle, better housing etc
• means more housing shortages and pollution • more medical fees to pay by the taxpayer, taxes rise • state won't be able to pay everyone's pensions |