Biology - B5

ECG is way we can evaluate electrical impulses from the heart, also called electocardiogram. Another way to moniter the heart would be using an echocardiogram which makes an image of the heart beating using ultrasound. SAN makes atria contract by producing impulses that spread across it, the AVN makes the ventricles contract by relaying impulses which spread over them. Factors that alter heartrate are adrenaline and nerves connecting heart-brain. The blood groups are A (have A-agglutinins - agglutinins are marker proteins on red blood cells) Group B (has B- Agglutinins) AB (a- and b agglutinins) and O(no agglutinins). People with A blood have anti-b antibodies (so cant accept blood from B/AB as have B-agglutins) B group have anti A antibodies, AB have no antibodies and O have A&B antibodies so can only accept from O. O is common blood group. If you're rhesus+ you have rhesus proteins and if you,re rhesus- then you don't. Fish breath under water as they gulp h2o and push it out of the gill flap, then the o2 is asorbed by fine fillaments and put into blood supply, this way fish can carry out gaseous exchange, fish cant breath air as not dense enough to go in fillaments.Kidneys work by.1 Ultrafilteration-blood squeezed in tubule at high pressure seperaing water and molecules 2 Selective reabsorbsion- useful stuff put back in(some h20, ions and all sugar) 3 Excretion of waste- waste pass at bladder as urine (excess h2o, ions and urea). Salt + water regulated by excreting waste salt in urine and reabsorbing needed amount of h2o. Dialysis works out of body,blood put in machine and there is a permable mebreane which stops blood and dialysis fluid mixing, waste diffuse in dialysis fluid and Na and C6H12O6 is put back in .blood,must have 2-3 sessions(3 hours each).The menstrual cycle is maintained by hormones, FSH stimulates egg to ripen, once ripe release of oestrogen(thickens lining) then LH release causes ovulation(releses egg), menustration is break of lining.

Ossifacation is when the cartlidge in your bones is replaced by Ca and P salts as we age, so adults only have cartlidge at end of bones to protect them. Cartlidge and bone are living tissue so ability to repair/regrow themselves.Heart made from powerful muscle and is given 02 and c6h12o6 by cornary artery, 1)heart relaxes blood eneters both atria from veins 2) atria contract so blood pushed in ventricles opening cuspid valves 3) ventricles cxontract at bottem so blood gpes up in arteries so semi lunar valves open forcing cuspid to closo, blood is now in arteries.   Heart rate is controlled by pacemaker cells in right atrium - produce electrical impulses to make heart contract, if excercise heartrate increased to match suppy for o2. Smoking(CO3 reduces O2 carried in RBC), Alcahol (low blood presuure and high blood cholestreal), Diet(block arteries), Stress and drugs(high blood pressure) all contribute to heart disease. There are 4 types of blood Plasma -transports dissolved substances and hormones around body as liquid-, White blood cells - nucleous makes antibodies to destroy pathagens, and can change shape to engulf them-, Red blood cell- bioconcave shape, no nucleus so more space to transport o2 which can bind with heomoglobin to carry o2 around body-, Platelet - give out chemicals and proteins + enzymes dissolve in blood which react forming mesh of fibrin fibres sealing wound,cell fragments have enzymes which speed up clotting. Blood clots to block pathogens and stop losing excess blood, for healthy blood clotting need Vitamin C, and normal clotting vitiman K needed, unhealthy cloting due to alcohol and cranberries. Thrombosis is when blood clots on undamaged vessels so need anticougulant - asprin,warafin to reduce clotting. Haemophilia is inherited blood fails to clot due to faulty clotting protein.

The alveoli is needed for gaseous exchange, it has a good blood supply, large surface area,moise thin permable surface perfect for diffusing in o2 and out co2.Diseases related to the lungs are: Abestosis - industrial, inhaling abestos fibres reducing GE, symptoms are breathless and hard to absorb enough o2. Brochitis- inflammation of brochi, Cystic Fibrosis-inherited too much production of mucus so hard to breath, Lung Cancer- lifestyle,tar causes mutations, Pneumonia-inflamation of lungs,virul or bacterial infection, Asthma- ariways easily swollen, brochioles narrow harder to breath, treat with inhaler, asthma attack is when bronchioles irratated, constrict, muscles tighten and mucus increse so hard to breath and wheeze ect. ADH (antidiuretic hormone) controls permibility of renal tubes to absorb right amount of h2o e.g of Negative feedback. So if low h20 blood level,brain detcts, kidney absorb more water, give concentrated small urine and normal blood water maintained. If high blood water level give out dilute large urine. For infertile couples there is a lot of options, FSH injected as fertility drug stimulate egg ripen and release, Artificail insemination for chance of fertalisation, IVF embroyo dish, but low sucess/expensive,Egg donation has donars genetic info, Ovary transplant if own ovaries dont function, Surragacy works but mother may be emotionally attached. 2 methods of screening; ultrasound image sex, defects revealed & amniocentesis analyses cells found in amniocentisis fluid in foetus to find chromosone abnorbilities but has risk of miscarraige, people think scans gives choice of ending babies life & is unethical. Growth controlled by HGH, too much giantism and too less dwarfism. the hormone is released from pituary gland energy for growth is released from fat stores & stimulates long bone growth. Growth factors;health; diseases ;genes; amount of HGH; Diet-protein for muscle grow, Ca/vitamin D for bone grow. Exercise so bones dense/hard.

Long bones are strong and lighter and have a hollow shaft( conatins bone marrow and bloood vessels) and the head has air spaces and covered in hard but slippery cartlidge to lubricate movement.Joint is where two bones meet here are the types; Fixed -boney plates fise together(skull), Hinge-allow movement in one direction(elbow and knee), Ball and socket allow rotation(hips and shoulder).Ligaments join bones to bones, tendons attach muscles -which contract making bones move- to bones. Joints can be replaced artificially, pros are can be tailered, goves mobility/independence,no rejection, Cons are cant replace disease/weak bones, major surgery.The arm has antoganistic muscles; bend arm , bicep contract,tricep relax and straight arm oppisite. Elbow joint acts as fulcrum, bicep only contrat small distance as close to elbow, radiaus bone acts as lever so hand moves more.An open CS (circularity system) blood flows in body cavity and o2 is directly put in specialised tubules for GE, closed CS is where blood flows in vessels. Single CS has 2 chambers and passes once in heart for one full curcuit wheras in double travels twice and has 4 chambers oxgenated blood and deoxgenated travel seperate (ox in left and deox on right) Galen says thta blood flows like tide in liver and heart, Harvey said heart pump blood to vessels,arteries carry blood in high pressure and veins have valves Blood pressure is lower in capileries and lowest in veins. During ventalation inhalation occurs - ICM(intercoastal muscled contract, ribcage moves up and out, volume chest big, pressure falls so ait rush in. During exhalation ICM relax, ribcage moves down, chest volume smal, increased pressure so air rushes out. Spirometre used to meausre breathing of 1. tidal air- normal breath 2.Vital air capcity-max breath in and out 3. Residual air-amount of air still in lungs at end of Vital capicity air.Defecation - rid of solid waste. Excretion-rid of stuff made in body i.e, CO2- breathing rate incresed if too much made by respiring, Urea-made when AA break down in liver, Sweat- has h20 and salt which are excrete by sweat glands on skin.

There are three types of skelontons, internal has framework,flexible,grows with bones,,muscles attched and made from bone and cartldge.Sharks have internal made out of just cartlidge so less rigid but light/flexible. External hard ones AKA exoskeletons made of chitin and heavy/inflexible, and worms have no skeleton. There are three main fractures simple-bone breaks clean, compound- breaks slightly, greenstick-breaks through skin and muslce. Pulse rate is when heart contracts putiing blood under pressure and sent to arteries surge is called heart beat/pulse rate.The heart can suffer problems - irregular heart beat but can get artificial pacemaker ,-hole in heart allows deox and ox blood to mix so o2 dont get to tissues,can be closed with surgery-faulty valves replaced artificial-Coronary artery blocked so bypass surgery gets blood vessels from leg. Heart assist devices reduce work by muscles till recover.Heart transplant pro-health/life expectancy improves. con is risky operation, have to take drugs stop rejection and big wait. Organ donation can be done alive and dead, but long waiting list and risk of rejection so have to be matched well to patient. have to carry donar cary some say iots unethical, mechnical implants have to be small and compact and should not react with skin, has good battery supply recharge out of body. Have to take immunosuspressent drugs so more vunrable to diseases. Some say should pay to donate organs but poor shall sell their health, we have opt-in system, doner has to have no chance of survival.Blood tranfusion saves lives,donar card, some say unethical/against religion, have to match blood group. Amoeba small enough to get o2 from diffusion, human thorax made up of; trachea; bronchi; ICM; bronchioles; alveoli;pleural membrane and diaghram. Bodys defences; goblet cells make mucas to trap dust; ciliated cells move mucas up; alveoli dead end so dirt trap. In plant only the meristems grow; shoot-apical and root- lateral,<--plants=mitosis.