NEET BIOLOGY

Detailed explanation-1: -Remember that we breathe out carbon dioxide. This carbon dioxide is generated through the process of cellular respiration, which has the reverse chemical reaction as photosynthesis. That means when our cells burn food (glucose) for energy, carbon dioxide is released.

Detailed explanation-2: -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).

Detailed explanation-3: -When we exhale, we breathe out less oxygen but more carbon dioxide than we inhale. The carbon we breathe out as carbon dioxide comes from the carbon in the food we eat.

Detailed explanation-4: -While photosynthesis requires carbon dioxide and releases oxygen, cellular respiration requires oxygen and releases carbon dioxide. It is the released oxygen that is used by us and most other organisms for cellular respiration. We breathe in that oxygen, which is carried through our blood to all our cells.

Detailed explanation-5: -Breathing is a chemical change as during breathing oxygen is taken inside and carbon dioxide and water are released. Physical change is the change of that matter where only the appearance or molecular arrangement of matter changes without changing its composition.