Respiration Uses
Biology: Cambridge International GCSE Supplement, topic 12.1.1
Energy
Respiration happens in every living cell. It releases energy from food and is controlled by enzymes. Organisms need energy for many reasons:
Construction
- To make larger molecules from smaller molecules. For example:
- Proteins can be made from amino acids in plants and animals.
Contraction
- To contract the muscles of animals, allowing them to move.
Homeostasis
- To keep the body temperature of warm-blooded animals (mammals and birds) relatively constant.
Growth
- Organisms grow through cell division.
- This process requires energy.
Active transport
- Movement of substances into or out of cells up a concentration gradient (from low to high concentration) requires energy.
Nerve impulses
- Sending nerve impulses through the nervous system uses energy from respiration.