AP Biology  BR: Explain the connection between the cardiovascular system and…  Respiratory System  Digestive System  Excretory System  Objectives  Students will explain the internal transport system in animals  HW

AP Biology December 13, 2011  BR:  Why would the heart rate increase during physical activity?  Objectives  Students will explain the internal transport system in animals  HW  Chp 36 notes

AP Biology Circulatory Systems

AP Biology

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 that’s easy!  diffusion  If you are many-celled that’s 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 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 Learning Check  List several advantages and disadvantages of open and closed circulatory systems

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

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

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 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 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 Learning Check  Explain how defective valves in the heart can lead to altered cardiovascular function

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

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

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 Learning Check  Describe how the structure of arteries, veins, and capillaries are all well suited for their respective functions

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  Filters interstitial fluid through lymph nodes  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 Learning Check  Explain the connection between the circulatory and lymphatic systems

AP Biology December 12, 2011  BR: Explain the variables we are testing in this lab  Ind variable (changing)  Dep variable (measuring)  Control  Objectives  Students will collect data to explain cardiac physiology  HW  Lab Analysis

AP Biology Lab 10: Circulatory Physiology Description: study factors that affect heart rate and blood pressure - body position - level of activity

AP Biology Lab 10: Circulatory Physiology  Part A: Resting BP  Practice measuring blood pressure and obtain average resting BP  Decide who will be the ONE test subject for the remainder of the lab  Part B: Fitness Test  Test 1- change in BP reclining to standing  Test 2- resting standing pulse  Test 3- resting reclining pulse  Test 4- change in pulse rate reclining to standing  Test 5- recovery rate

AP Biology Measuring Pulse  What is a pulse and where do you measure pulse?  Pulse  Pressure wave of blood entering circulation when the ventricles contract  Monitored at “pressure points” in arteries where pulse is easily palpated  Pulse averages 70– 76 beats per minute at rest

AP Biology Measuring Arterial Blood Pressure Figure 11.20a

AP Biology Measuring Arterial Blood Pressure Figure 11.20c

AP Biology March 25, 2011  BR:  Describe how the structure of the heart allows it to function well as a pump  Objectives  Students will explain the internal transport system in animals  Student will conduct a lab to determine function of the cardiovascular system  HW  Quiz Monday- Review notes/ SG chps 40, 41,42, 44, 48, 49  Chp 43 due monday