AP BIOLOGY

Detailed explanation-1: -Ventilation, or breathing, is the movement of air through the conducting passages between the atmosphere and the lungs. The air moves through the passages because of pressure gradients that are produced by contraction of the diaphragm and thoracic muscles.

Detailed explanation-2: -The process of breathing, or respiration, is divided into two distinct phases. The first phase is called inspiration, or inhaling. When the lungs inhale, the diaphragm contracts and pulls downward. At the same time, the muscles between the ribs contract and pull upward.

Detailed explanation-3: -Breathing is a mechanical Process. In breathing, an organism takes in oxygen from its environment and released carbon-dioxide. Breathing involves the transport of oxygen and carbon dioxide between the external environment and the body cells. This process is also called pulmonary respiration.