Transport

Match it! Select the correct answer from the pull down...Good luck!

These carry oxgenated blood BACK to the heart.

These cells are what attack infection in the body.

Below the trachea, the ___________ form the first branches into the lungs.

These are what keeps blood flowing in one direction in and out of the heart.

The human heart has how many chambers?

What would happen if the trachea became blocked?

Alveoli need to be extremely thin so that...

These carry blood AWAY from your heart.