Question

The end-product of respiration is
A. Carbon dioxide
B. Water
C. Both carbon dioxide and water
D. None of the above

Answer 1

Hint: Respiration is a biochemical process of a chain of chemical reactions which enables all living entities to synthesize and utilize the required amount of energy in order to sustain. It is also referred to as a metabolic process in which energy is acquired during the exchange of gases.

Complete answer:
Respiration in plants is a process in which the chemical energy is produced in the form ATP molecule. This process takes place by the oxidation of simple sugar i.e., glucose which is formed in cells due to the breakdown of more complex carbohydrates. Therefore the presence of this glucose is then converted into energy and produces 3 carbon compounds and water as by-products.
The process of respiration in plants that takes place in mitochondria of the cell along with the presence and utilization of oxygen is termed as aerobic respiration. The presence of oxygen is utilized to break down the chemical bonds in glucose in order to liberate high volumes of energy and produce carbon dioxide and water as end-products during respiration.
This method of respiration can be represented by a simple chemical equation:
$6C_6{H}_{12}{O}_6+6O_2\to 6C{O}_2+6H_{2}O+36ATP$

According to the above equation, it is showing that six molecules of carbon dioxide ($C{O}_2$​), six molecules of water ($H_{2}O$) and 36 molecules of ATP is obtained as an end-product, when six molecules of glucose ($C6H12O6$​) is reacted with six molecules of oxygen ($O_2$​).

Hence, the correct answer is option (C).

Note: Another type of respiration is known as Anaerobic Respiration. In this process, respiration takes place with the absence of oxygen in which the chemical bonds in glucose are partially broken to obtain less energy and Carbon dioxide. This process is also known as intramolecular respiration and it occurs in organisms like parasitic worms, certain bacteria and yeast.