2. AP Biology 2008-2009 Circulatory Systems

3. AP Biology

4. Exchange of materials  Animal cells exchange material across their cell membrane  If you are a 1-cell organism that’s easy!  diffusion  If you are many-celled that’s harder

5. 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

6. AP Biology In circulation…  What needs to be transported  nutrients  from digestive system  respiratory gases  O 2 & CO 2 from & to gas exchange systems: lungs, gills  Wastes  from cells  water, salts, nitrogenous wastes (urea)  protective agents  immune defenses  white blood cells & antibodies  blood clotting agents  regulatory molecules  hormones

7. AP Biology Circulatory systems  All animals have:  fluid = “blood”  tubes = blood vessels  muscular pump = heart openclosed hemolymphblood

8. AP Biology Open circulatory system  invertebrates  insects, arthropods, mollusks  Blood goes out of vessels

9. AP Biology Closed circulatory system  invertebrates  earthworms, squid, octopuses  All vertebrates  blood confined to vessels closed system = higher pressures

10. 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 What’s 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 and birds

11. AP Biology Evolution of vertebrate circulatory system fishamphibianreptilesbirds & mammals AA V V VV V AAAA A V 2 chamber3 chamber 4 chamber

12. AP Biology Evolution of 4-chambered heart convergent evolution Advantages – allows for:  increase body size  protection from predation  bigger body = bigger stomach for herbivores  endothermy  can colonize more habitats  flight  decrease predation & increase prey capture  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

13. AP Biology Vertebrate cardiovascular system  Chambers  atrium = receive blood  ventricle = pump blood out  Blood vessels  arteries = carry blood away from heart  arterioles  veins = return blood to heart – they have valves  venules  capillaries = thin wall, exchange / diffusion  capillary beds = networks of capillaries

14. AP Biology Blood vessels arteries arterioles capillaries venules veins artery arteriolesvenules veins

15. AP Biology Arteries: Built for high pressure pump  Arteries  thicker walls  narrower diameter  elasticity  Largest is the Aorta

16. AP Biology Veins: Built for low pressure flow  Veins  thinner-walled  wider diameter  blood travels back to heart at low velocity & pressure  blood flows by skeletal muscle contractions squeeze blood through veins  valves  in larger veins one-way valves allow blood to flow only toward heart  Largest vein: Vena Cava Open valve Blood flows toward heart Closed valve

17. AP Biology valves

18. AP Biology http://www.youtube.com/watch? NR=1&v=O2HEwdnF4o4&featu re=endscreen Valves and muscle pumps

19. AP Biology Capillaries: Built for exchange  Capillaries  very thin walls  diffusion exchange between blood & cells

20. AP Biology Controlling blood flow to tissues  controlled by sphincters  Amount of blood depends on need  During exercise – more to legs  During digestion- more to stomach, etc.  capillaries in brain, heart, kidneys & liver usually filled to capacity sphincters opensphincters closed

21. AP Biology Mammalian heart Coronary arteries to neck & head & arms

22. AP Biology http://www.mydr.com.au/heart- stroke/animation-how-your- heart-pumps http://www.youtube.com/watch? v=Rj_qD0SEGGk Path of blood through the heart

23. AP Biology Heart beating  http://www.youtube.com/watch?v=FRd3 K6LkhWs&feature=related http://www.youtube.com/watch?v=FRd3 K6LkhWs&feature=related

24. AP Biology AV SL AV Heart valves  4 valves in the heart  flaps of connective tissue  prevent backflow  Atrioventricular (AV) valve  between atrium & ventricle  prevents blood flowing back into atria  “lub”  Semilunar valves  between ventricle & arteries (aorta/pulmonary)  prevent backflow into ventricles “dub” AV valves -Right – tricuspid Left –bicuspid or mitral

25. AP Biology AV SL AV Lub-dub, lub-dub  Heart sounds  closing of valves  “Lub”  blood against closed AV valves  “Dub”  blood against semilunar valves  Heart murmur  defect in valves causes hissing sound when blood squirts backward through valve

26. AP Biology Mammalian circulation What do blue vs. red areas represent? pulmonary systemic

27. AP Biology Pulse  Pulse measures the rate of the heart beat  Average for adults is 70-72X min. but varies with size, exercise, etc.

28. AP Biology Pacemaker – the S.A. node  Sino-atrial node is the pacemaker – controls the rate of the heart

29. AP Biology http://www.youtube.com/watch? v=IR0nWe47eek Pacemaker

30. AP Biology Cardiac cycle systolic ________ diastolic pump (peak pressure) _________________ fill (minimum pressure)  contraction phase  systole  ventricles pumps blood out  relaxation phase  diastole  atria refill with blood 110 ____ 70 Average Blood Pressure

31. AP Biology Measurement of blood pressure  High Blood Pressure (hypertension)  if top number ( systolic pumping) > 150  if bottom number ( diastolic filling) > 90

32. AP Biology Causes of hypertension  Can be controlled: diet (salt, fat) Habits (smoking) Weight (obesity)  Age, genetics, unknown

33. AP Biology EKG- measures electrical currents in heart

34. AP Biology

35. fibrillation  Irregular contraction of chambers Defibrillator shocks heart Into regular contractions

36. AP Biology Coronary Arteries  Bring blood (O 2 and glucose) to the heart muscle. (veins bring it back) aorta Left ventricle

37. AP Biology atherosclerosis Blockage of artery Blockage leads to ANGINA PECTORIS–pain in chest

38. AP Biology Atherosclerosis  https://www.youtube.com/watch?v=fLo nh7ZesKs https://www.youtube.com/watch?v=fLo nh7ZesKs

39. AP Biology angioplasty  stents

40. AP Biology Coronary arteries – heart attack Myocardial infarction -causes damage to heart muscle

41. AP Biology Coronary artery bypass bypass surgery

42. AP Biology Bypass

43. AP Biology Fibrillation  http://www.youtube.com/watch?v=f7GiJ 5P8JYg http://www.youtube.com/watch?v=f7GiJ 5P8JYg  http://www.youtube.com/watch?v=HyQj pQf_eME http://www.youtube.com/watch?v=HyQj pQf_eME

44. AP Biology Capillaries  http://www.youtube.com/watch?v=Q530 H1WxtOw http://www.youtube.com/watch?v=Q530 H1WxtOw

45. AP Biology Lymphatic system  Parallel circulatory system  transports white blood cells  collects interstitial fluid & returns to blood