Circulatory System Professor Andrea Garrison Biology 11 Illustrations 2010 Pearson Education, Inc. unless otherwise noted Circulatory System 1
Circulatory System Circulatory system = Cardiovascular system = heart, blood vessels & blood Circulatory System 2
Function = homeostasis Transport O 2 /CO 2 Food/wastes Fluids Hormones Regulate ph Water balance Temperature Close connection with immune response Circulatory System Circulatory System 3
Blood ~ 5 liters in adult Plasma Cellular elements Circulatory System 4
Blood Plasma ~ 55% of blood volume 90% water 10% solutes Blood proteins Nutrients Wastes Gases Hormones Circulatory System 5
Blood Cellular elements ~ 45% of blood volume Circulatory System 6
Blood Red blood cells 5 million/cc (=ml) Carry O 2 Produced in bone marrow Biconcave No nucleus Live ~ 120 days Circulatory System 7
Blood White blood cells 4,000 11,000/cc Protection from disease Produced in bone marrow Have nucleus Long-lived Circulatory System 8
Blood Platelets 200,000 400,000/cc Form blood clots Produced in bone marrow Cell fragments Circulatory System 9
Heart Pumps blood to body s cells Circulatory System National Heart Lung Blood Institute, www.nhlbi.nih.gov 10
Heart Anatomy Circulatory System; From Wikimedia Commons, Diagram of the human heart, created by Wapcaplet in Sodipodi. Cropped by Yaddah to remove white space (this cropping is not the same as Wapcaplet's original crop). 11
Heart Anatomy 4 chambers 2 atria 2 ventricles Valves Atrioventricular (AV) valves Semilunar valves Right semilunar valve Right AV valve Left AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 12
Heart Anatomy 4 chambers 2 atria Receive blood 2 ventricles Pump blood out of heart Right semilunar valve Left AV valve Right AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 13
Heart Anatomy Valves Prevent backwards flow of blood Right semilunar valve Left AV valve Right AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 14
Heart Double Circuit Circulatory System 15
Blood Vessels Arteries carry blood away from heart Veins return blood to heart Capillaries in between Every organ has its own capillary network Circulatory System 16
Blood Vessels Circulatory System 17
Blood Vessels Capillaries Gas and nutrient exchange Very small vessels Walls one cell thick Effective diffusion Narrow lumen One cell at a time Effective diffusion Circulatory System 18
Blood Vessels Capillaries Gas and nutrient exchange Very small vessels Walls one cell thick Effective diffusion Narrow lumen One cell at a time Effective diffusion Circulatory System 19
Blood Circuit artery arteriole heart capillaries vein venule Circulatory System 20
Double Circuit Circulatory System 21
Heart Anatomy Right semilunar valve Left AV valve Right AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 22
Blood Flow through the Heart Circulatory System 23
Blood Flow through Heart Circulatory System 24
Blood Flow through Heart Circulatory System 25
Blood Flow through Heart Circulatory System 26
Blood Flow through Heart Circulatory System 27
Blood Flow through Heart Circulatory System 28
Blood Flow through Heart Circulatory System 29
Blood Flow through Heart Circulatory System 30
Blood Flow through Heart Circulatory System 31
Blood Flow through Heart Circulatory System 32
Blood Flow through Heart Circulatory System 33
Blood Flow through Heart Circulatory System 34
Heartbeat Intrinsic to heart muscle Regulated by sinoatrial node (pacemaker) Its own intrinsic rate of beating Sends electric impulses so all cells beat w/it Involuntary nervous system or heart rate Circulatory System 35
Heartbeat Circulatory System 36
Heartbeat Circulatory System 37
Heart Rate Resting heart rate 60-100 bpm (~ 72 bpm healthy non-athlete) Heart alternates between contraction and relaxation Contraction = systole Relaxation = diastole Circulatory System 38
Cardiac Cycle Circulatory System 39
Cardiac Cycle Circulatory System 40
Cardiac Cycle Circulatory System 41
Heart Valves Open when P behind > P in front Right semilunar valve Close when P in front > P behind Left AV valve Right AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 42
Heart Valves Healthy valves insure one-way flow Tendons attach AV valves to ventricle wall Semilunar valves have little pressure in front Right semilunar valve Right AV valve Left AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 43
Heart Valves Make heart sounds when they close Healthy sounds Damaged valves Allow backflow Cause heart murmur Right semilunar valve Right AV valve Left AV valve Left semilunar valve Circulatory System; modified from National Cancer Institute, NIH, www.cancer.gov 44
Blood Flow through Vessels Systole Ventricles contract Blood leaves heart via arteries Arterial pressure Diastole Ventricles relax Arterial pressure Blood flow surges in arteries Circulatory System 45
Blood Flow through Vessels Side note: Blood pressure Systolic pressure during systole Diastolic pressure during diastole Systolic P/diastolic P Average <120/<80 High 140/90 or greater Circulatory System 46
Blood Flow through Vessels Surging and pressure with distance from heart No difference in pressure in capillaries and veins during systole and diastole Blood flow smooth in capillaries and veins Circulatory System 47
Blood Flow through Vessels Blood pressure lowest in veins Heartbeat cannot return blood to the heart Venous return depends on other mechanisms Skeletal milking Respiratory pumping Circulatory System 48
Return of Blood through Veins Skeletal milking Functions in arms and legs Muscle contraction around veins squeezes blood towards heart Veins have one-way valves Blood is milked towards torso Circulatory System 49
Return of Blood through Veins Respiratory pumping Inhalation decreases pressure around heart Sucks blood through abdominal and chest cavities toward heart Circulatory System 50
Return of Blood through Veins Respiratory pumping Inhalation decreases pressure around heart Sucks blood through abdominal and chest cavities toward heart Circulatory System 51
Vasodilation/Vasoconstriction Blood vessels can dilate or constrict Involuntary nervous system Controls blood pressure Fight or flight response Local tissue control Constrict to blood flow in cold weather to avoid heat loss Dilate to blood flow in warm weather to cool off For healing of injured tissues Circulatory System 52
Cardiovascular Disease Diseases of the heart and blood vessels Kill over 1 million people in US each year Circulatory System 53
Atherosclerosis Circulatory System 54
Coronary Artery Disease Circulatory System 55
Cerebral Vascular Disease Stroke Blockage of blood vessel in brain Blood clot or fatty deposits Bleeding blood vessel in brain Rupture due to weak vessel wall or high blood pressure Circulatory System 56
Peripheral Artery Disease Blockage of blood vessels in legs blood flow to legs and feet Pain in legs when walking Greater risk of heart attack/stroke Circulatory System 57
Hypertension High blood pressure Can harden arteries blood flow to heart Chest pain Heart failure inability of heart to pump enough blood to organs Can rupture blood vessels Stroke Kidney damage Circulatory System 58
Heart Health Don t smoke Exercise regularly Maintain a healthy weight Healthy diet Low in saturated fats No trans fats Low cholesterol Low sodium High fiber (lowers cholesterol) Circulatory System 59