Presentation on theme: "AP Biology 2008-2009 Circulatory Systems AP Biology."— Presentation transcript:
AP Biology Circulatory Systems
Exchange of materials Animal cells exchange material across their cell membrane fuels for energy nutrients oxygen waste (urea, CO 2 ) If you are a 1-cell organism thats easy! diffusion If you are many-celled thats harder
AP Biology Overcoming limitations of diffusion O2O2 CHO aa CH CO 2 NH 3 aa O2O2 CH aa CO 2 NH 3 O2O2 aa CH aa CHO O2O2 Diffusion is not adequate for moving material across more than 1-cell barrier
AP Biology In circulation… What needs to be transported nutrients & fuels from digestive system respiratory gases O 2 & CO 2 from & to gas exchange systems: lungs, gills intracellular waste waste products from cells water, salts, nitrogenous wastes (urea) protective agents immune defenses white blood cells & antibodies blood clotting agents regulatory molecules hormones
AP Biology BLOOD!!! What is it good for???? 55% of blood volume = plasma 45% of blood volume = cells, platelets ERYTHROCYTES (rbcs) Last about 120 days No organelles! Produced in red bone marrow, sternum, ribs, some long bones old rbcs removed by spleen and liver Hemoglobin on rbcs is what carries O 2 -> lack of hemoglobin = anemia Each rbc has 280 million molecules of hemoglobin. How many hem. mol. in your body if have 5 million rbcs per mL of blood and usually have body volume of 5L? <-MATH ATTACK!
AP Biology BLOOD, cont. Leukocytes (wbcs) Immunity! TWO TYPES: 1.Granular (produced in bone marrow) *Neutrophils (most abundant) – phagocytic *Eosinophils – allergic reactions *Basophils – allergic reactions (histamines) 2.Agranular *Lymphocytes – produce antibodies *Monocytes (largest WBC) – phagocytic LEUKEMIA = cancer of wbcs (overabundance of wbcs – leads to weakness/impaired clotting)
AP Biology Never Let Monkeys Eat Bananas!!! N eutrophils L ymphocytes M onocytes E osinophils B asophils
AP Biology Circulatory systems All animals have: circulatory fluid = blood tubes = blood vessels muscular pump = heart openclosed hemolymphblood
AP Biology Open circulatory system Taxonomy invertebrates insects, arthropods, mollusks Structure no separation between blood & interstitial fluid hemolymph
AP Biology Closed circulatory system Taxonomy invertebrates earthworms, squid, octopuses vertebrates Structure blood confined to vessels & separate from interstitial fluid 1 or more hearts large vessels to smaller vessels material diffuses between blood vessels & interstitial fluid closed system = higher pressures
AP Biology Vertebrate circulatory system Adaptations in closed system number of heart chambers differs 4 chamber heart is double pump = separates oxygen-rich & oxygen-poor blood; maintains high pressure Whats the adaptive value of a 4 chamber heart? 234 low pressure to body low O 2 to body high pressure & high O 2 to body
AP Biology Evolution of vertebrate circulatory system fishamphibianreptilesbirds & mammals AA V V VV V AAAA A V 2 chamber3 chamber 4 chamber Birds AND mammals! Wassssup?!
AP Biology Evolution of 4-chambered heart convergent evolution Selective forces increase body size protection from predation bigger body = bigger stomach for herbivores endothermy can colonize more habitats flight decrease predation & increase prey capture Effect of higher metabolic rate greater need for energy, fuels, O 2, waste removal endothermic animals need 10x energy need to deliver 10x fuel & O 2 to cells
AP Biology Vertebrate cardiovascular system Chambered heart atrium = receive blood ventricle = pump blood out Blood vessels arteries = carry blood away from heart arterioles veins = return blood to heart venules capillaries = thin wall, exchange / diffusion capillary beds = networks of capillaries
AP Biology Arteries: Built for high pressure pump Arteries thicker walls provide strength for high pressure pumping of blood narrower diameter elasticity elastic recoil helps maintain blood pressure even when heart relaxes
AP Biology Veins: Built for low pressure flow Veins thinner-walled wider diameter blood travels back to heart at low velocity & pressure lower pressure distant from heart blood must flow by skeletal muscle contractions when we move squeeze blood through veins valves in larger veins one-way valves allow blood to flow only toward heart Open valve Blood flows toward heart Closed valve
AP Biology Capillaries: Built for exchange Capillaries very thin walls lack 2 outer wall layers only endothelium enhances exchange across capillary diffusion exchange between blood & cells
AP Biology Controlling blood flow to tissues Blood flow in capillaries controlled by pre-capillary sphincters supply varies as blood is needed after a meal, blood supply to digestive tract increases during strenuous exercise, blood is diverted from digestive tract to skeletal muscles capillaries in brain, heart, kidneys & liver usually filled to capacity sphincters opensphincters closed Why?
AP Biology Exchange across capillary walls Arteriole Blood flow Venule Lymphatic capillary Interstitial fluid Fluid & solutes flows out of capillaries to tissues due to blood pressure bulk flow Interstitial fluid flows back into capillaries due to osmosis plasma proteins osmotic pressure in capillary BP > OPBP < OP 15% fluid returns via lymph 85% fluid returns to capillaries What about edema? Capillary
AP Biology Lymphatic system Parallel circulatory system transports white blood cells defending against infection collects interstitial fluid & returns to blood maintains volume & protein concentration of blood drains into circulatory system near junction of vena cava & right atrium
AP Biology Lymph system Production & transport of WBCs Traps foreign invaders lymph node lymph vessels (intertwined amongst blood vessels)
AP Biology Mammalian circulation What do blue vs. red areas represent? pulmonary systemic
AP Biology Mammalian heart Coronary arteries to neck & head & arms
AP Biology Coronary arteries bypass surgery
AP Biology AV SL AV Heart valves 4 valves in the heart flaps of connective tissue prevent backflow Atrioventricular (AV) valve between atrium & ventricle keeps blood from flowing back into atria when ventricles contract lub Semilunar valves between ventricle & arteries prevent backflow from arteries into ventricles while they are relaxing dub
AP Biology AV SL AV Lub-dub, lub-dub Heart sounds closing of valves Lub recoil of blood against closed AV valves Dub recoil of blood against semilunar valves Heart murmur defect in valves causes hissing sound when stream of blood squirts backward through valve
AP Biology With every beat of your heart…. Watch me go! SA (Sinoatrial) node (pacemaker) = in wall of right atrium – when this fires, action potential spreads to both atria via gap junctions in intercalated discs AV (Atrioventricular) node = in lower right atrium – acts as delay/relay – sends message to ventricles to contract Cardiac center in medulla communicates with heart to regulate (hormones can speed up/slow down)
AP Biology Issues of the heart What Women ThinkThe Facts 60% Cancers35% Heart disease 19% Heart disease23% All cancers 13% Dont know(4% breast) 4% Other causes20% Other causes 2%Stress8% Strokes 1% Old age4% Pulmonary dis. 1% Smoking4% Pneumonia/flu 3% Accidents 3% Diabetes What actually kills women????
AP Biology Issues of the heart cont. Heart murmur – improper closing of heart valve(s) – can lead to need for repair/replacement Cardiomegaly – enlarged heart – ranges from mild to severe (need for replacement) hole in heart – improper closing of septum between L and R ventricles (open before birth b/c babies dont need lungs until born) – foramen ovale Hypoplasia – only one side of heart functions properly Brugada Syndrome – sudden cardiac death – irregular heart rhythms (genetic) Mitral stenosis – narrowing of mitral valve – decreased blood flow to body SO MANY MORE -CHECK THEM OUT
AP Biology Cardiac cycle systolic ________ diastolic pump (peak pressure) _________________ fill (minimum pressure) 1 complete sequence of pumping heart contracts & pumps heart relaxes & chambers fill contraction phase systole ventricles pumps blood out relaxation phase diastole atria refill with blood 110 ____ 70
AP Biology Measurement of blood pressure High Blood Pressure (hypertension) if top number ( systolic pumping) > 150 if bottom number ( diastolic filling) > 90
AP Biology Bloody well ask some questions, already!