cell respiration. They produce a large number of ATP molecules. So they are called as power houses of the cell or ATP factory of the cell . It helps the cells to maintain normal concentration of calcium ions.
It regulates the metabolic activity of the cell. . TYPES OF RESPIRATION Respiration involves exchange of gases between the organism and the external environment. The plants obtain oxygen from their environment and release carbon dioxide and water vapour.
This exchange of gases is known as external respiration . It is a physical process. Biochemical process occurs within cells where the food is oxidized to obtain energy, this is known as cellular respiration . .
Aerobic respiration Aerobic respiration is the type of celluar respiration in which organic food is completely oxidized with the help of oxygen into carbon dioxide, water and energy. It occurs in most plants and animals. C H O + 6O → 6CO + 6H O + ATP Stages of Aerobic respiration a. Glycolysis (Glucose splitting): It is the breakdown of one molecule of glucose ( carbon) into two molecules of pyruvic acid ( carbon).
Glycolysis takes place in cytoplasm of the cell. It is the first step of both aerobic and anerobic respiration. b. Krebs Cycle: This cycle occurs in mitochondria matrix.
At the end of glycolysis, molecules of pyruvic acid enter into mitochondria. The oxidation of pyruvic acid into CO and water takes place through this cycle. It is also called Tricarboxylic Acid Cycle (TCA). c.
Electron Transport Chain: This is accomplished through a system of electron carrier complex called electron transport chain (ETC) located on the inner membrane of the mitochondria. NADH+H + and FADH molecules formed during glycolysis and Krebs cycle are oxidised to NAD + and FAD to release the energy via electrons. The electrons, as they move through the system, release energy which is trapped by ADP to synthesize ATP. This is called oxidative phosphorylation .
In this process, O the ultimate acceptor of electrons gets reduced to