Circulatory System Transport

1. Circulatory SystemTransport

2. Why do we need a circulatory system? • connects all other systems together • supplies in • fuel (sugars) + raw materials • digestive system • oxygen • respiratory system • waste out • urea • excretory system • CO2 • respiratory system • need to pick up & deliver the supplies & wastes around the body • circulatory system

3. Simple organisms When your body is only 2-cell layers thick, you can get supplies in and waste out just through Diffusion – passive transport • all cells within easy reach of fluid • MUST have moist membranes Jellyfish Hydra

4. Complex organisms • Circulatory system - made up of 3 parts • organ • heart – pump • tissues & cells • blood vessels • arteries • veins • capillaries • blood • red blood cells • white blood cells • plasma • platelets

5. Vertebrate Heart • 4-Chambered heart • atria (atrium) – top of heart • thin wall • collection chamber • receive blood • ventricles – bottom of heart • thick wall pump • pump blood out Two sides separated by septum Allows separation of oxygenated and deoxygenated blood

6. Superior vena cava aorta Pulmonary artery Pulmonary veins R. atrium L. atrium valve valve L. ventricle R. ventricle Inferior vena cava septum

7. Lub-dub, lub-dub • 4 one-way valves in the heart • flaps of connective tissue • prevent backflow • Heart sounds • closing of valves • “Lub” • force blood against closed AV valves • “Dub” • force of blood against semilunar valves • Heart murmur • leaking valve causes hissing sound • blood squirts backward through valve SL AV AV

8. Cardiac Cycle ventriclesfill How is this reflected in blood pressure measurements? systolic ________ diastolic chambers fill pump(peak pressure) _________________ fill(minimum pressure) 110 ________ 70 ventriclespump

9. Measurement of blood pressure if systolic > 150 or if diastolic > 90 hypertension =(high blood pressure)

10. Circulatory SystemBlood Vessels

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

12. 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 • feel a pulse

13. 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 • why low pressure? • far from heart • 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

14. Structure-function relationship • Capillaries • LOTS of surface area • very thin walls • allows diffusion of materials across capillary • O2, CO2, H2O, food, waste body cell waste CO2 O2 food

15. Circulation of Blood Pulmonary Circulationto/from the lungs • 2 part system • Circulation to lungs • blood gets O2 from lungs • drops off CO2 to lungs • brings O2-rich blood from lungs to heart • Circulation to body • pumps O2-rich blood to body • picks up nutrients from digestive system • collects CO2 & cell wastes lungs heart body Systemic Circulationto/from the body

16. Vertebrate circulatory system • 2 part system lungs Pulmonary arteriesto lungs Pulmonary veins from lungsto heart heart vena cavas – veins from bodyto heart aorta - artery to body body

17. Stops along the way… • Lungs - pulmonary • pick up O2 / clean out CO2 • Small Intestines • pick up nutrients from digested food (aa, ss, fa) • Large Intestines • pick up water from digested food • Liver - hepatic • clean out worn out blood cells – recycle into bile

18. More stops along the way… • Kidneys - renal • filters out wastes (urea) • extra salts & water • Bone • picks up new red blood cells • Spleen • picks up new white blood cells

19. ATP CO2 O2 Circulatory System & Homeostasis • Homeostasis • keeping the internal environment of the body balanced • need to balance food & O2 in • need to balance energy (ATP) production • need to balance CO2 & waste out • Exercise • heart beat faster – MC Lab • need more ATP • bring in more O2 & food; remove more CO2 & waste out • Disease • poor lung or heart function = heart beat faster • need to work harder to bring in O2 & food & remove wastes food waste

20. Circulatory SystemBlood

21. Blood & blood cells • Blood is a tissue of fluid & cells • plasma • liquid part of blood • dissolved salts, sugars, proteins (hormones, enzymes, and more (urea, aa, water) • cells • red blood cells (RBC) • transport O2 in hemoglobin (a protein) • white blood cells (WBC) • defense & immunity • platelets • blood clotting – complex process; requires Calcium

22. Red blood cells • Small round cells – NO nucleus • produced in bone marrow • 5 liters of blood in body • 5-6 million RBC in drop of human blood • last 3-4 months (120 days) • filtered out by liver • ~3 million RBC destroyed each second and recycled into bile

23. 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

24. Cardiovascular health bypass surgery • Risk Factors • genetics • diet • high animal fat - saturated • exercise & lifestyle • smoking • lack of exercise