Essentials of Human Anatomy Physiology Chapter 37 1

Essentials of Human Anatomy & Physiology Chapter 37 -1 & 37 -2 The Circulatory System Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Human Circulatory System • The Heart • The Blood Vessels • Blood Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Human Circulatory System pulmonary vein pulmonary artery lungs head & arms aorta main vein Right Left liver digestive system kidneys legs Circulatory System Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Parts of the Heart • The Atria -Receiving Chambers • The Ventricles -Pumping Chambers • The Valves -Controls Flow • The Septum -Divides the Heart Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Human Heart Structure Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Human Heart Structure Superior Vena Cava Large vein that brings oxygen-poor blood from the upper part of the body to the right atrium Aorta Brings oxygen-rich blood from the left ventricle to the rest of the body Pulmonary Arteries Bring oxygen-poor blood to the lungs Pulmonary Veins Bring oxygen-rich blood from each of the lungs to the left atrium Left Atrium Pulmonary Valve Prevents blood from flowing back into the right ventricle after it has entered the pulmonary artery Right Atrium Tricuspid Valve Prevents blood from flowing back into the right atrium after it has entered the right ventricle Inferior Vena Cava Vein that brings oxygen-poor blood from the lower part of the body to the right atrium Aortic Valve Prevents blood from flowing back into the left ventricle after it has entered the aorta Mitral Valve Prevents blood from flowing back into the left atrium after it has entered the left ventricle Left Ventricle Septum Right Ventricle Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Heart: The Vital Pump • At REST, the heart pumps about 5 QUARTS of blood a minute. • During EXTREME EXERTION (exercise) it can pump 40 quarts a minute. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Flow Through the Heart Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Control of Heart: Nervous System • Medulla oblongata regulates rate • Sensory cells stretch when too fast • Pressure drops when beat is too low Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Two Pathways of Blood Flow • Pulmonary Circulation – Carries blood to lungs and back • Systemic Circulation – Carries blood to body and back Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Capillaries of head and arms Superior vena cava Aorta Pulmonary artery Pulmonary vein Capillaries of right lung Capillaries of left lung Inferior vena cava Capillaries of abdominal organs and legs

Types of Blood Vessels • • • Arteries -Carry blood away from the Heart -The Aorta is the largest artery Veins -Carry blood toward the Heart -Veins contain valves -The Vena Cava is the largest vein Capillaries -Known as the “Distribution Pipes” Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Double Pump System Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Coronary Vessel Structure Serous membrane Continuous with blood vessels Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Arteries: Blood Away From Heart – – Large Thick-walled, Muscular Elastic Oxygenated blood • Exception Pulmonary Artery – Carried under great pressure – Steady pulsating Arterioles: smaller vessels, enter tissue Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Capillaries: Exchange Takes Place – – Smallest vessel Microscopic Walls one cell thick Nutrients and gases diffuse here Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Veins: Blood Toward the Heart – Carries blood that contains waste and CO 2 • – – Exception pulmonary vein Blood not under much pressure Valves to prevent much gravity pull Venules: larger than capillaries Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Artery vs. Vein Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Composition of Blood • The Plasma (Fluid) makes up 55% of the blood volume. • The Solids (Cells) make up 45% of the blood volume. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Plasma • 97% Water • Other 3% -Antibodies and Proteins - Nutrients and Wastes Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Solids • Red Blood Cells -Carry oxygen -Contain Hemoglobin • White Blood Cells -Attack bacteria & other invaders • Platelets -Control the blood clotting process Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Plasma • Body contains 4 -6 L • Consists of – – Water Red Blood Cells Plasma White blood cells and platelets Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Plasma It also contains useful things like; • carbon dioxide A strawcoloured liquid that carries the cells and the platelets which help blood clot. • glucose • amino acids • proteins • minerals • vitamins • hormones • waste materials like urea. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Plasma Platelets White blood cells Red blood cells Whole Blood Sample Placed in Centrifuge Blood Sample That Has Been Centrifuged

Plasma Platelets White blood cells Red blood cells Whole Blood Sample Placed in Centrifuge Blood Sample That Has Been Centrifuged

Plasma Platelets White blood cells Red blood cells Whole Blood Sample Placed in Centrifuge Blood Sample That Has Been Centrifuged

Your Blood: Fluid Transport • a Tissue • 50% water • 4% dissolved substances Liquid Portion Carries • Blood cells – Erythrocytes (RBC - red blood cells) – Leucocytes (WBC - white blood cells) • Platelets (non cellular particles) • Proteins – Enzymes – Hormones – Endocrine System • Nutrients - Digestive System • Gases - Respiratory System • Inorganic salts Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Oxygen in the Blood • Hemoglobin, iron containing molecule • Loosely picks up oxygen in the lungs • Loses oxygen in areas low in oxygen (diffuses) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Carbon Dioxide in the Blood • Hemoglobin carries CO 2 also • CO 2 is a waste product of cellular work • 70% of CO 2 combines with water • The rest travels to the lungs Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

The Composition of Blood • • 50% Water 45% Erythrocytes 4% Plasma with Substances 1% Leukocytes + Platelets Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Erythrocytes: Red Blood Cells a biconcave disc that is round and flat without a nucleus contain hemoglobin, a molecule specially designed to hold oxygen and carry it to cells that need it. can change shape to an amazing extent, without breaking, as it squeezes single file through the capillaries. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Erythrocytes: Red Blood Cells • Transporters of – Oxygen – Carbon Dioxide • RBC – Lack a nucleus – Contain hemoglobin – Disk-shaped • RBC are produced in red bone marrow of – – ribs, humerus, femur, sternum, and other long bones • Lives for 120 days • Old RBC are destroyed in liver and spleen Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Leukocytes: White Blood Cells there are many different types and all contain a big nucleus. the two main ones are the lymphocytes and the macrophages ‘eat’ and digest microorganisms. some lymphocytes fight disease by making antibodies to destroy invaders by dissolving them. other lymphocytes make antitoxins to break down poisons. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Leukocytes: White Blood Cells • WBC fight infection – • • • Less abundant Large cells Some live for months – • • Attack foreign substances Most just a few days Several types ALL contain nuclei Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Platelets are bits of cell broken off larger cells. Platelets produce tiny fibrinogen fibres to form a net. This net traps other blood cells to form a blood clot. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Platelets • • • PLATELETS are for CLOTTING blood Cell fragments Produced in bone marrow Short life span (1 week) Fibrin (sticky network of protein fibers) – Form a web trapping blood cells Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Clotting Break in Capillary Wall Clumping of Platelets Clot Forms Blood vessels injured. Platelets clump at the site and release thromboplastin. Thromboplastin converts prothrombin into thrombin. . Thrombin converts fibrinogen into fibrin, which causes a clot. The clot prevents further loss of blood. . Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Pressure • Blood against the blood vessel’s walls – The systolic pressure refers to • the pressure recorded while the ventricles pump the blood. – The diastolic pressure refers to • the pressure recorded as the ventricles fill with blood. • A normal blood pressure is 120/80 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Types Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Types Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Mixing Blood Types • Plasma contains proteins that correspond to the shape of the different antigens • If you mix one type with the wrong one, you get CLUMPING • Type O is the universal donor • Type AB is the universal acceptor Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Mixing Blood Types Blood Type of Donor Blood Type of Recipient A B AB O Unsuccessful transfusion Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Successful transfusion

Circulatory System Summary away from the heart. The walls of an artery Arteries take blood ______ muscular walls and elastic fibres. Veins carry are made up of thick _____ towards blood ____ the heart and also have valves. The _____ link capillaries arteries and veins, and have a one cell thick wall. Blood is made up of plasma four main things ______, the liquid part of the blood; Red Blood oxygen Cells to carry ______; White Blood cells to protect the body from platelets disease and _____ to help blood clot. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Blood Flow Through the Heart Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings