Question

Write short notes on aerobic respiration and anaerobic respiration.

Answer 1

The process of breakdown and conversion of food nutrients into useful energy inside a cell is called cellular respiration. In this process, energy released is used up to maintain the different biological functions and processes of the body. This process takes place in a cell or occurs at the cellular level, it is known as cellular respiration.

Complete answer:
The chain of metabolic processes which converts the chemical energy contained in the food into energy in the form of ATP is known as cellular respiration. It breaks down the complex nutrient elements into simpler elements such as carbohydrates or sugars are broken into carbon dioxide and water. It occurs inside the cell and the released energy which further fuels the different types of cellular activity. Cellular respiration occurs in the cells through two types of processes which are aerobic respiration and anaerobic respiration.
The type of cellular respiration that occurs in the presence of oxygen is called aerobic respiration. The process requires oxygen to produce ATP or energy molecules. The important reactants of this process are carbohydrates or sugars obtained from food are broken down into pyruvates in the glycolysis reaction and then enters the Krebs cycle to fully oxidize in order to produce ATP, water and carbon dioxide. The process includes an electron transport system which oxygen acts as the final acceptor of electrons. It is the common and useful method of energy generation in the living cells. This method of cellular respiration generates about thirty-six ATP molecules.
Anaerobic respiration is the respiration that occurs in absence of oxygen or when oxygen is not present. In this process, the end product is lactic acid or ethanol and not carbon dioxide, along with ATP molecules. This process is very common in yeast and bacteria. Yeast is able to switch to anaerobic mode of cellular respiration when oxygen is absent. Yeast are able to produce ethanol during anaerobic respiration. In human anaerobic respiration occurs in the muscle fibers and lactic acid is produced. The net energy production in aerobic respiration is very low, about two molecules of ATP are produced for every glucose molecule. The final electron is an inorganic acceptor such as nitrate or sulfate instead of oxygen as oxygen is absent during the process.

Note: Aerobic respiration is the common and efficient mode of cellular respiration in most types of cells which produces about thirty-six molecules of ATP after catabolic reaction of glucose in presence of oxygen. The end product of this reaction is ATP as well as carbon dioxide and water. Anaerobic respiration occurs in microorganisms like bacteria and yeast and produces energy in the form of ATP in absence of oxygen.