Question | Answer |
What makes up the main organs of the respiratory system? | lungs |
What path does the oxygen take to reach the lungs? | It goes from the nose or mouth through the trachea to the lungs. |
What is the job of the circulatory system? | to take blood to all parts of the body |
Which part of the circulatory system pumps blood to all body parts? | the heart |
Why doesn't blood leaving the heart mix with blood entering the heart? | Blood leaves through the heart through arteries and returns to the heart through veins. |
What makes blood follow a one-way path through the heart? | Valves allow flow in only one direction. |
Why is it easy for gases to pass between air sacs and blood? | Air sacs have very thin walls. |
Which blood vessels take blood away from the heart? | arteries |
Which blood vessels in the lungs help your body take in and give off gases? | capillaries |
What do you think would happen if blood entering the heart mixed with blood leaving the heart? | Blood carrying oxygen would mix with blood carrying carbon dioxide. The body might not get all the oxygen it needed. |
Which is a waste product of cells? | carbon dioxide |
lungs | main organ of the respiratory system |
capillaries | tiny blood vessels that allows gases and nutrients to pass from blood to cells |
heart | The muscle that pumps the blood through blood vessels to all parts of the body. |
arteries | Blood vessels that carry blood away from the heart. |
veins | Large blood vessels that return blood to the heart. |