1. Science Module 7 th Grade

2. Body Systems Circulatory System 7 th Grade Science

3. Background

4. Circulatory System Structures Heart Blood Vessels –Arteries –Veins –Capillaries Blood

5. Circulatory System Function The overall function of the circulatory system is to transport materials throughout the body toward and away from particular target organs and tissues.

6. Two Pathways Pulmonary Circulation –Carries blood to lungs and back to the heart Systemic Circulation –Carries blood to body and back to the heart

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

8. Arteries: carries blood way from heart Arteries: carries blood Away from heart –Large –Thick-walled, Muscular –Elastic –Oxygenated blood  Exception Pulmonary Artery –Carried under great pressure –Steady pulsating

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

11. Veins: Veins: Carries blood to heart –Carries blood that contains waste and CO 2  Exception pulmonary vein –Blood not under much pressure –Valves to prevent much gravity pull

12. Your Heart: The Vital Pump At REST, the heart pumps about 5 QUARTS of blood a minute. At REST, the heart pumps about 5 QUARTS of blood a minute. During EXTREME EXERTION (exercise) it can pump 40 quarts a minute. During EXTREME EXERTION (exercise) it can pump 40 quarts a minute.

13. Heart: Structure and Function Keeps blood moving Keeps blood moving Large organ composed of Cardiac muscle Large organ composed of Cardiac muscle

14. Structure of Heart Four chambers Four chambers –Two upper (Atrium)  Right Atrium  Left Atrium –Two lower (Ventricles)  Right Ventricle  Left Ventricle

15. Bloods Path Through the Heart Both Atrium fill at same time Both Atrium fill at same time –Right atrium receives oxygen POOR blood from body via the vena cavas –Left atrium receives oxygen RICH blood from lungs through four pulmonary veins After filled with blood atriums contract, pushing blood into ventricle After filled with blood atriums contract, pushing blood into ventricle

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

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

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

19. Erythrocytes (RBC) Transporters of Transporters of –Oxygen –Carbon Dioxide

20. Leukocytes (WBC) WBC fight infection WBC fight infection –Attack foreign substances Less abundant Less abundant Large cells Large cells

21. Platelets PLATELETS are for CLOTTING blood PLATELETS are for CLOTTING blood Cell fragments Cell fragments Produced in bone marrow Produced in bone marrow Fibrin (sticky network of protein fibers) Fibrin (sticky network of protein fibers) –Form a web trapping blood cells

22. Section 37-2 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..

23. Blood Types Massive loss of blood requires a transfusion Massive loss of blood requires a transfusion Four Types Four Types –A–A–A–A –B–B–B–B –AB –O–O–O–O Inherited from your parents Inherited from your parents

24. Blood Types

25. What happens when you mix blood types? Plasma contains proteins that correspond to the shape of the different antigens Plasma contains proteins that correspond to the shape of the different antigens If you mix one type with the wrong one, you get CLUMPING If you mix one type with the wrong one, you get CLUMPING Type O is the universal donor Type O is the universal donor Type AB is the universal acceptor Type AB is the universal acceptor

26. What Makes Our Blood Type?

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

28. Getting to the Heart of the Matter http://studyjams.scholastic.com/studyjams/jams/science/human- body/circulatory-system.htm