Question

The main waste products of plants are
A. $CO_2$ and $NO_2$
B. $CO_2$ and water vapour
C. $CO_2$ and $O_2$ and water vapour
D. None of the above

Answer 1

Hint: The waste products of plants are excreted through photosynthesis, respiration, and transpiration. Excess water is removed by the process of transpiration.

Complete step by step answer:
First we should know about excretion in plants to answer this question. Dependent on certain life processes, living creatures sustain life. These processes of life help to control their regular activities. One of them is excretion. In the cells of living organisms, metabolism takes place, resulting in both beneficial and harmful materials. Toxin accumulation can harm the organism. Therefore, all these biochemical wastes are eliminated from their bodies by living beings, and this process is called excretion. Organisms, such as animals, have an advanced and sophisticated excretion system. But, plants lack a well-developed excretory system like animals. They may not have separate excretory organs. Thus, in plants, excretion is not so complicated.
Now, let us find the solution from the options-
- $NO_2$ is not an excretory product of plants. Plants use $NO_2$ as nitrate which is formed by nitrogen fixation. Therefore, the option A is incorrect.
- $CO_2$ and water vapour is not only the excretory product of plants. Therefore, the option B is incorrect.
- Two gas waste products, i.e. oxygen during photosynthesis and carbon dioxide during respiration, are released by plants. In plants, excretion of gaseous waste occurs by stomatal pores on leaves. For respiration, oxygen emitted during photosynthesis is used, and for photosynthesis, carbon dioxide emitted during respiration is used. Excess water is also excreted from the body of the plant via the stomatal pores and from the fruit and stem surfaces as water vapour. The water removal mechanism is called transpiration.
Thus, the correct answer is option (C) $CO_2$ and $O_2$ and water vapour

Note: Some waste materials stored in plant parts, such as barks, roots, leaves, etc., are gums, oils, latex, resins, etc. Various types of stored waste products are oil derived from orange, eucalyptus, jasmine, latex from rubber and papaya trees and gums from acacia. They even excrete it into the soil occasionally. Via diffusion, excretion of aquatic plants takes place.