The aortic valve, which is located between the left ventricle and the aorta, functions to ' prevent blood from flowing backward'.
The structures that contain membranes across which oxygen and carbon dioxide diffuse are the 'alveoli'.
Answer 1: The left ventricle prevents the blood from flowing backward to the body.
Explanation:
The deoxygenated blood of the body enters the heart and then it follows a certain path in the heart and then gets filtered in the heart and moves out of the heart only when it is oxygenated.
The aortic valve helps in holding the oxygen rich blood in the left chamber of the heart before it is being released from the heart to the whole body.
Answer 2. Alveoli
Explanation:
The alveoli can be defined as the small sac which helps in the gaseous exchange. This structure helps in exchanging the oxygen and carbon dioxide.
The carbon from the body is released out of the body and the oxygen from the outside is inhaled for the body.
The oxygen from the lungs reaches the heart so as to supply oxygen rich blood to the vital parts of the body.
