Respiration
- The process by which a living being utilizes the food to get energy is called respiration.
- Respiration is an oxidation reaction that involves sequential degradation of food and generation of energy.
- Mitochondria is the site of respiration and the energy released is stored in the form of ATP (Adenosine triphosphate)
- The respiratory system provides the route by which the oxygen present in our environment gains entry into the body and the carbon dioxide produced is excreted.
Breathing: This whole process of exchange of gases is called breathing
STEPS OF RESPIRATION:
1. Breaking down glucose into pyruvate:
- This step happens in the cytoplasm. Glucose molecules are broken down into pyruvic acid.
- Glucose molecule is composed of 6 carbon atoms, while pyruvic acid is composed of 3 carbon atoms.
- Fate of Pyruvic Acid: Further breaking down of pyruvic acid takes place in mitochondria and the molecules formed depend on the type of respiration in a particular organism.
Respiration is of two types, viz. aerobic respiration and anaerobic respiration.


TYPES OF RESPIRATION:
Aerobic Respiration:
- This type of respiration happens in the presence of oxygen.
- Pyruvic acid is converted into carbon dioxide.
- Energy is released and water molecules are also formed at the end of this process.

Anaerobic Respiration:
- This type of respiration happens in the absence of oxygen.
- Pyruvic acid is either converted into ethyl alcohol or lactic acid.
- Ethyl alcohol is usually formed in case of anaerobic respiration in microbes; like yeast or bacteria.
- Lactic acid is formed in some microbes as well as in the muscle cells.