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Humus is :- (i) Dark coloured amorphou...

Humus is :-
(i) Dark coloured amorphous substance
(ii) Highly resistant to microbial action and undergoes decomposition at an extremely slow rate
(iii) Being colloidal in nature
(iv) Acts as a reservoir of nutrients

A

(i), (ii) are incorrect

B

i, iii & v are correct but iii incorrect

C

i, iii, iv are correct

D

All are incorrect

Text Solution

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The correct Answer is:
To solve the question regarding humus, we will evaluate each of the four statements provided and determine their accuracy based on the characteristics of humus. ### Step-by-Step Solution: 1. **Evaluate Statement (i)**: "Dark coloured amorphous substance" - Humus is indeed a dark-colored substance. The term "amorphous" means that it does not have a definite shape or structure, which is true for humus as it is a complex mixture of organic materials. - **Conclusion**: This statement is **True**. 2. **Evaluate Statement (ii)**: "Highly resistant to microbial action and undergoes decomposition at an extremely slow rate" - This statement is misleading. While humus does have some resistance to further decomposition, it is not highly resistant to microbial action. In fact, microbes play a significant role in breaking down organic matter into humus. The decomposition of organic matter into humus happens relatively quickly due to microbial activity. - **Conclusion**: This statement is **False**. 3. **Evaluate Statement (iii)**: "Being colloidal in nature" - Humus does exhibit colloidal properties. Colloids are substances where the particle size is between 1 to 1000 nanometers, and they do not fully dissolve but remain suspended in a solution. Humus can hold water and nutrients in a colloidal form, which is essential for soil health. - **Conclusion**: This statement is **True**. 4. **Evaluate Statement (iv)**: "Acts as a reservoir of nutrients" - Humus is known for its ability to retain nutrients and minerals, making it a crucial component of fertile soil. It acts as a reservoir for essential nutrients that plants need for growth. - **Conclusion**: This statement is **True**. ### Final Conclusion: Based on the evaluations: - Statement (i) is True. - Statement (ii) is False. - Statement (iii) is True. - Statement (iv) is True. Thus, the correct statements about humus are (i), (iii), and (iv).
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