Circulatory System in Animals: Essential Components and Functions

1. Circulatory Systemin Animals

2. Feeding the Need for Energy • Supplies in • fuel (sugars) • digestive system • oxygen • respiratory system • Waste out • CO2 • respiratory system • Need to pick up & deliver the supplies & wastes around the body • circulatory system

3. Circulatory system • Made up of 3 parts • organ • heart • tissues & cells • blood • red blood cells • blood vessels(vascular system) • arteries • veins • capillaries

4. Circulatory systems • All animals have: • muscular pump = heart • tubes = blood vessels • circulatory fluid = “blood” open closed hemolymph blood

5. SL AV AV Vertebrate circulatory system • 2 part system lungs arteryto lungs vein from lungsto heart heart vein from bodyto heart artery to body body

6. Circulation of Blood in Mammals Circulationto lungs • 2 part system • Circulation to lungs • blood gets O2 from lungs • brings O2-rich blood back to heart • Circulation to body • pumps O2-rich blood to body • picks up nutrients from digestive system • brings CO2& cell wastes from body to heart lungs heart body Circulationto body

7. Stops along the way… • Lungs • pick up O2 / clean out CO2 • Small Intestines • pick up nutrients from digested food • Large Intestines • pick up water from digested food • Liver • clean out worn out blood cells

8. More stops along the way… • Kidneys • filters out wastes (urea) • excess salts, sugars & water • Bone • picks up new red blood cells • Spleen • picks up new white blood cells

9. Mammalian Heart • 4-Chambered heart • atria (atrium) • thin wall • collection chamber • receive blood • ventricles • thick wall pump • pump blood out leftatrium rightatrium rightventricle leftventricle

10. SL AV AV Heart valves • 4 valves in the heart • flaps of connective tissue • prevent backflow • AV valve • between atrium & ventricle • keeps blood from flowing back into atrium when ventricle pumps • “lub” • Semilunar valves • between ventricle & arteries • prevent backflow from arteries into ventricles • “dub” Heart murmur • leaking valve causes hissing sound • blood squirts backward through valve

11. Electrical signals • heart pumping controlled by electrical impulses • signal also transmitted to skin = EKG stimulates ventricles to contract from bottom to top, driving blood into arteries allows atria to empty completely before ventricles contract

12. Measurement of blood pressure • High Blood Pressure (hypertension) • if top number (pumping) > 150 • if bottom number (filling) > 90

13. Blood vessels arteries veins artery arterioles venules arterioles capillaries venules veins

14. Arteries: Built for their job • Arteries • blood flows away from heart • thicker walls • provide strength for high pressure pumping of blood • elastic & stretchable • maintains blood pressure even when heart relaxes

15. Major arteries aorta carotid= to head to brain & left arm to right arm to body pulmonaryartery pulmonaryartery=to lungs coronary arteries

16. Coronary arteries bypass surgery

17. Veins: Built for their job Blood flows toward heart • Veins • blood returns back to heart • thinner-walled • blood travels back to heart at low speed & pressure • blood flows because muscles contract when we move • squeeze blood through veins • valves in large veins • in larger veins one-way valves allow blood to flow only toward heart Openvalve Closed valve

18. Major Veins superiorvena cava= from upper body pulmonaryvein= from lung pulmonaryvein = from lung inferiorvena cava= from lower body

19. Capillary: Where all the action is • Capillaries • very thin walls • allows exchange of materials across capillary • O2, CO2, H2O, food, waste • diffusion

20. Blood & blood cells • Blood is a tissue of fluid & cells • plasma • fluid • dissolved salts, sugars, proteins, and more • cells • red blood cells (RBC) • transport O2 in hemoglobin • white blood cells (WBC) • defense & immunity • platelets • blood clotting

21. Blood Cell production ribs, vertebrae, breastbone & pelvis • Stem cells • “parent” cells in bone marrow • mature into many different types of cells white blood cells white bloodcells red bloodcells

22. Red blood cells • Small round cells • produced in bone marrow • lose nucleus & mitochondria • more space for hemoglobin • iron-containing protein that transports O2 • last 3-4 months (120 days) • filtered out by liver • ~3 million RBC destroyed each second • replaced by 3 million more produced each second • 5-6 million RBC in tiny drop of human blood • 5 liters of blood in body

23. Hemoglobin • Protein which carries O2 O2 O2 O2

24. emergency repair of circulatory system Blood clotting chemicalemergencysignals plateletsseal the hole fibrin protein fibersbuild clot

25. Cardiovascular disease • Atherosclerosis & Arteriosclerosis • deposits inside arteries (plaques) • develop in inner wall of the arteries, narrowing their channel • increase blood pressure • increase risk of heart attack, stroke, kidney damage normal artery hardening of arteries

26. Cardiovascular health bypass surgery • Genetic effects • Diet • diet rich in animal fat increases risk of CV disease • Exercise & lifestyle • smoking & lack of exercise increases risk of CV disease

27. Cardiovascular health (U.S. 2001)

28. Heart Disease Heart disease death rates 1996-2002Adults ages 35 and older

29. Women & Heart Disease Death rates for heart disease per 100,000 women, 2002 • Heart disease is 3rd leading cause of death among women aged 25–44 years & 2nd leading cause of death among women aged 45–64 years. Risk factors • Smoking • Lack of exercise • High fat diet • Overweight

30. Any Questions??