AP BIOLOGY

Detailed explanation-1: -When you inhale (breathe in), air enters your lungs, and oxygen from that air moves to your blood. At the same time, carbon dioxide, a waste gas, moves from your blood to the lungs and is exhaled (breathed out). This process, called gas exchange, is essential to life.

Detailed explanation-2: -The lungs and respiratory system allow us to breathe. They bring oxygen into our bodies (called inspiration, or inhalation) and send carbon dioxide out (called expiration, or exhalation). This exchange of oxygen and carbon dioxide is called respiration.

Detailed explanation-3: -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-4: -Diaphragmatic breathing requires contraction of the diaphragm and is also called deep breathing. Costal breathing requires contraction of the intercostal muscles and is also called shallow breathing.

Detailed explanation-5: -The breathing cycle can be divided into three basic stages including rest, inspiration, and expiration which are discussed separately below.