Circulatory System Physical Science 9/16/2011

Inside the Heart The right side of the heart gets oxygen-poor blood (blue arrows) from the body & pumps it to the lungs, where it picks up oxygen. The left side of the heart gets oxygen-rich blood (red arrows) from the lungs and pumps it to the body cells. The valves between the atria and ventricles only open in one direction.  Which way does blood flow between an atrium and a ventricle?

Heartbeats Your heart has two sides, each of which has an atrium and a ventricle. Each atrium is an area where blood first enters the heart before being sent to body parts. Each ventricle works to pump blood out of the heart. Blood always comes in an atrium and leaves thru a ventricle. During a heartbeat, both atria contract at the same time, then relax. Then both ventricles contract at the same time, then relax.

Arteries Blood vessels that carry blood away from the heart, to the lungs or to the body.  In our traffic analogy, what kinds of roads are most similar to arteries?

Veins Blood vessels that transport blood back to the heart from the lungs or body.

Capillaries Smallest blood vessels that form an extensive network in the organs, connecting arteries to veins.  In our traffic analogy, what kinds of roads are most similar to capillaries?

Heartbeats Revisited During a heartbeat, both atria contract at the same time, then relax. Then both ventricles contract at the same time, then relax. When chambers of your heart contract and relax, what effect does this have on your blood?

Review… Oxygen-poor blood comes into the __________ (atrium/ventricle), flows through a valve into the __________ (ventricle/atrium), then flows out through a(n) __________ (artery/vein) to the lungs. Oxygen-rich blood flows through the same order on the other side of the heart, then flows out to the body cells, transporting oxygen and nutrients.

Section 3-1 CYU (on a separate sheet to TURN IN) Diagram the pathway of blood thru the human heart. Compare the three types of blood vessels (arteries, veins, and capillaries). Fish have gills lined with capillaries. Water contains dissolved oxygen. Explain what you think happens when water flows over the blood supply in fish gills. Going back to our traffic map analogy, which streets are like capillaries?