AP BIOLOGY

Detailed explanation-1: -Cells need oxygen for the efficient use of glucose in cellular respiration. Most organisms use this method to obtain energy. Oxygen binds to parts of glucose molecules, which release water, carbon dioxide, and energy. After all, this is done, the organism uses the energy to produce adenosine triphosphate (ATP).

Detailed explanation-2: -In a process called diffusion, oxygen moves from the alveoli to the blood through the capillaries (tiny blood vessels) lining the alveolar walls. Once in the bloodstream, oxygen gets picked up by the hemoglobin in red blood cells.

Detailed explanation-3: -Oxygen gives our cells the ability to break down food in order to get the energy we need to survive. Although other animals may use different organs to breathe with, they all get oxygen into their bodies through respiration.

Detailed explanation-4: -While oxygen is essential for the survival of cells, excess or too little oxygen can lead to adverse health consequences. Oxygen supply temporarily reduces in muscles during intense exercise and under such conditions the cells adapt their metabolism to low oxygen levels.