The Circulatory System You Gotta Have Heart The Circulatory System

Engage Walt Disney’s Hemo the Magnificent Scene 3 – The Heart Scene 4 – Lubb-Dubb

Explore How does exercise affect heart rate? Circulatory System Relay Color Your Heart

Hemo the Magnificent Scene 6 – The Capillaries

Circulatory System Consists of… Blood Vessels Blood Heart

Circulatory System BLOOD VESSELS

Two Pathways Pulmonary Circulation Systemic Circulation Carries blood to lungs and back Systemic Circulation Carries blood to body and back

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

Your Blood Vessels: Pathway of Circulation 3 types of vessels Arteries Capillaries Veins

Artery vs. Vein

Arteries: carries 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

Capillaries Smallest vessel Microscopic Walls one cell thick Nutrients and gases diffuse here

Veins: Carries blood to heart Carries blood that contains waste and CO2 Exception pulmonary vein Blood not under much pressure Valves to prevent much gravity pull Venules: larger than capillaries

Varicose Veins Damaged Valves in Veins

Circulatory System BLOOD

What is Blood? Blood Simulation

The Blood Body contains 4-6 L Consists of Water Red Blood Cells Plasma White blood cells and platelets

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

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

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

Parts of the Blood

Your Blood: Fluid Transport 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 a Tissue 50% water 4% dissolved substances

Oxygen in the Blood Hemoglobin, iron containing molecule Loosely picks up oxygen in the lungs Loses oxygen in areas low in oxygen (diffuses)

Carbon Dioxide in the Blood Hemoglobin carries CO2 also CO2 is a waste product of cellular work 70% of CO2 combines with water The rest travels to the lungs

What does blood contain? 50% Water 45% Erythrocytes 4% Plasma with Substances 1% Leukocytes + Platelets

Erythrocytes (RBC) Transporters of RBC 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

Leukocytes (WBC) WBC fight infection Less abundant Large cells Attack foreign substances Less abundant Large cells Some live for months Most just a few days Several types ALL contain nuclei

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

Blood Clotting Break in Capillary Wall Blood vessels injured. Clumping of Platelets Platelets clump at the site and release thromboplastin. Thromboplastin converts prothrombin into thrombin.. Clot Forms Thrombin converts fibrinogen into fibrin, which causes a clot. The clot prevents further loss of blood..

Circulatory System HEART

Your 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.

Heart: Structure and Function Keeps blood moving Large organ composed of cardiac muscle, rich in mitochondria Enclosed by a sac PERICARDIUM

The Structures of the Heart Inferior Vena Cava Vein that brings oxygen-poor blood from the lower part of the body to the right atrium Tricuspid Valve Prevents blood from flowing back into the right atrium after it has entered the right ventricle Pulmonary Valve Prevents blood from flowing back into the right ventricle after it has entered the pulmonary artery Pulmonary Veins Bring oxygen-rich blood from each of the lungs to the left atrium 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 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 Atrium Right Atrium Left Ventricle Septum Right Ventricle

Structure of Heart (cont) Four chambers Two upper (Atria) Walls thinner Less muscular Two lower (Ventricles) Walls thicker More muscular Do more work

Blood Flow Through the Heart ©COPY 1997 HeartPoint

Bloods Path Through the Heart Both Atria fill at same time Rt atrium receives oxygen POOR blood from body from vena cava Left atrium receives oxygen RICH blood from lungs through four pulmonary veins After filled with blood atria contract, pushing blood into ventricle

Both ventricles contract Right ventricle contracts and pushes oxygen-poor blood toward lungs, against gravity, through pulmonary arteries

Bloods Path Through the Heart (cont) Left ventricle contracts and forces oxygen rich blood out of heart through aorta (largest vessel)

Hemo the Magnificent Scene 7 – Gatekeepers

Control of the Heart (Nervous System) Medulla oblongata regulates rate Sensory cells stretch when too fast Pressure drops when beat is too low

Heartbeat Regulation Force of blood from left ventricle into arteries (pulse) Pacemaker (SA Node), group of cells at top of right atrium Electrical impulse, signals BOTH atria to contract Triggers 2nd set of cells (AV Node)-base of the right atrium to send message to ventricles, they contract EkG – record of electrical changes in the heart

The Sinoatrial Node Contraction of Atria Contraction of Ventricles Sinoatrial (SA) node Conducting fibers Atrioventricular (AV) node

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

DISORDERS ATHEROSCLEROSIS Fatty deposits called plaque Builds up in walls of arteries Obstructs flow Also a risk if clot breaks free and blocks flow elsewhere

Disorders (cont) Hypertension High blood pressure Hearts works harder than necessary Increases risk of heart attack or stroke

Disorders (cont) Heart Attack Atherosclerosis in coronary artery Heart muscle begins to die Symptoms Nausea Shortness of breath Severe chest pain IMMEDIATE MEDICAL ATTENTION NECESSARY

Disorders (cont) Stroke Blood clot gets stuck in blood vessels leading to brain Brain cells die due to lack of oxygen Or blood vessel burst Can lead to paralysis, loss of ability to speak death

Current PREVENTION Recommendations Regular exercise Weight control Well balanced diet Do not smoke Diet low in saturated fat

Elaboration Blood Typing: To Clump or Not to Clump?

Blood Types Massive loss of blood requires a transfusion Four Types AB O Inherited from your parents

Blood Types

What happens when you mix 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

What Makes Our Blood Type?

Blood Transfusions Blood Type of Recipient Blood Type of Donor A B AB O A B AB O Unsuccessful transfusion Successful transfusion

Rh Factor Rhesus factor (Rh), also inherited Rh+ (have antigen) Rh- (NO antigen) Can cause complications in pregnancies mother Rh- 1st baby Rh+ : blood mixes with mother; mother’s body makes anti-Rh+ antibodies 2nd Rh + body attacks baby Now have medicine to prevent antibody formation