A hatching egg of chick is covered by plaster of paris. It is harmful for

Options

A. Mother
B. Respiration
C. Excretion
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Structure of an Egg**: A hatching egg, such as that of a chick, is covered by a protective layer called the shell. This shell is porous, meaning it has tiny holes that allow for the exchange of gases.

2. **Role of the Porous Shell**: The porous nature of the eggshell is crucial for the chick's development. It allows oxygen to enter the egg and carbon dioxide to exit, which are essential for the chick's respiration.

3. **Impact of Covering with Plaster of Paris**: If the hatching egg is covered with Plaster of Paris, it creates a solid, impermeable layer around the egg. This prevents the exchange of gases.

4. **Consequences of Impaired Gas Exchange**: Without the ability to exchange gases, the developing chick cannot receive the oxygen it needs for respiration. This can lead to suffocation and ultimately harm the embryo.

5. **Conclusion**: Therefore, covering a hatching egg with Plaster of Paris is harmful primarily because it obstructs respiration.

**Final Answer**: The hatching egg of a chick is harmed primarily in terms of respiration.

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