Which of the following best summarizes the function of the respiratory system?

Ato transport oxygen to cells and wastes away from cells.

Bto protect the organs in the chest cavity

Cto move oxygen from the air into the body and carbon dioxide from the body into the air

Dto provide a barrier between the body and the environment

C Which of the following is not true about the structure of an alveolus?

Ait has thick walls to trap gases that enter during breathing.

Bit has high surface area to allow lots of gas exchange.

Cit has a high concentration of oxygen and a low concentration of carbon dioxide.

A