1. © 2006 Plano ISD, Plano, TX Blood Vessels

2. © 2006 Plano ISD, Plano, TX The largest artery in the body, the aorta, is almost the diameter of a. a drinking straw b. a computer cable c. your big toe d. a garden hose

3. © 2006 Plano ISD, Plano, TX If all your blood vessels were laid end- to-end, they would extend for about a. 60,000 miles b. 6,000 miles c. 60 miles d. between 1-6 miles

4. © 2006 Plano ISD, Plano, TX Components of the Circulatory System blood connective tissue made of plasma and cells heart muscular pump to move blood blood vessels veins, arteries, capillaries that deliver blood to all parts of body

5. © 2006 Plano ISD, Plano, TX Blood Vessels arteries veins carry oxygen- rich blood from heart to body carry blood from organs and tissues to heart capillariescapillaries capillariescapillaries microscopic blood vessels located between arterioles and venules

6. © 2006 Plano ISD, Plano, TX

7. carry blood AWAY from the heart smallest arteries are called arterioles have thick, strong elastic walls Arteries

8. © 2006 Plano ISD, Plano, TX Arteries carry oxygen-rich blood throughout the body.

9. © 2006 Plano ISD, Plano, TX have thin, elastic walls with valves valves help veins return blood to the heart carry blood TO the heart Veins smallest veins are venules

10. © 2006 Plano ISD, Plano, TX Veins carry oxygen-poor blood back to the heart.

11. © 2006 Plano ISD, Plano, TX connect arteries and veins walls of capillaries are one cell layer thick surround every cell in the body CapillariesCapillaries CapillariesCapillaries site of gas exchange

12. © 2006 Plano ISD, Plano, TX Gas Exchange

13. © 2006 Plano ISD, Plano, TX tissue alveoli O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 CO 2 capillary CO 2 O2O2 Gas exchange occurs between the thin walls of the alveoli and the thin walls of the capillaries. CO 2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2 O2O2

14. © 2006 Plano ISD, Plano, TX Most are capillaries! Every pound of the human body has more than a mile of blood vessels!

15. © 2006 Plano ISD, Plano, TX all work together to bring oxygen to and remove carbon dioxide from the cells. Blood vessels, heart, lungs

16. © 2006 Plano ISD, Plano, TX

17. Identify. 1. 2. 3. 4. 5. 1. vein 2. venule 4. artery 5. arteriole 3. capillaries

18. © 2006 Plano ISD, Plano, TX Identify. 1. 2. 3. 4. 5.

19. © 2006 Plano ISD, Plano, TX

20. How does the structure of capillaries help them function efficiently in CO 2 /O 2 exchange?