Change in colour of algae according to a depth in sea is called :-

Options

A. Boh't effect
B. Gaudikov's effect
C. Fogg's effect
D. Pasteur effect

Answer

To solve the question "Change in colour of algae according to a depth in sea is called:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking for the term that describes the change in color of algae as the depth in the sea changes.

2. **Identify Key Terms**: The key terms in the question are "change in color," "algae," and "depth in sea." This indicates that we are looking for a specific effect related to light and algae.

3. **Consider the Options**: The options provided are:
- Bohort's effect
- Godikov's effect
- Fogg's effect
- Pasteur effect

4. **Recall Relevant Information**: From biological studies, it is known that algae can change color based on the light intensity available at different depths in the water. This phenomenon is often linked to the adaptation of algae to varying light conditions.

5. **Match with the Correct Term**: The term that specifically refers to the change in color of algae due to varying light conditions at different depths is known as **Godikov's effect**.

6. **Select the Answer**: Therefore, the correct answer to the question is **Godikov's effect** (Option 2).

### Final Answer:
The change in colour of algae according to a depth in sea is called **Godikov's effect**.

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