Question

Plants do not have respiratory organs due to the following reasons
I. Rate of respiration in plants is less than animals  
II. Loose packing of parenchyma cells  
III. Most cells of a plant have at least a part of their surface in contact with air  
IV. Transport of gases within the plant is more  

• A. II, III, IV
• B. I, II, III
• C. I, III, IV
• D. I, II, IV

Hint:

In plants, gas exchange occurs directly through the surface of cells, particularly in the leaves, and specialized respiratory organs are not required due to the low rate of respiration.

Answer 1

The Correct Option is B

Analysis of the Statements

Let's analyze the statements:

• I. Rate of respiration in plants is less than in animals: This statement is correct. Plants generally have a slower rate of respiration compared to animals, as their metabolic processes are less energy-demanding.
• II. Loose packing of parenchyma cells: This statement is correct. Parenchyma cells in plants are loosely packed, providing spaces for gas exchange within the plant tissues. This is why plants do not need specialized respiratory organs like animals.
• III. Most cells of a plant have at least a part of their surface in contact with air: This statement is correct. Since many plant cells are exposed to air, gas exchange can occur directly across the surface of the cells without the need for specialized respiratory organs.
• IV. Transport of gases within the plant is more: This statement is incorrect. While plants do transport gases (such as oxygen and carbon dioxide) via diffusion through stomata, the transport is not as efficient as in animals that have specialized respiratory organs. This is one of the reasons why plants do not require distinct respiratory organs.

Thus, the correct reasons are I, II, and III.

Therefore, the correct answer is (2) I, II, III.