Agar agar is obtained from

Options

A. Green Alga
B. Blue-green Algae
C. Brown Algae
D. Red Algae.

Answer

**Step-by-Step Solution:**

1. **Understanding Agar Agar**: Agar agar is a jelly-like substance that is widely used in various applications, including as a culture medium in laboratories, as a laxative, in desserts, and as a fruit preservative.

2. **Identifying the Source**: To determine where agar agar is obtained from, we need to look at the classifications of algae. The options provided are:
- Green alga
- Blue-green alga
- Brown alga
- Red alga

3. **Analyzing the Options**:
- **Green Alga**: This group does not produce agar agar.
- **Blue-green Alga**: This is also incorrect as it does not yield agar agar.
- **Brown Alga**: This group is not known for producing agar agar either.
- **Red Alga**: This is the correct option, as agar agar is derived from certain species of red algae.

4. **Specific Species**: The agar agar is specifically obtained from the cell walls of two species of red algae: **Gelidium** and **Gracilaria**. These species belong to the group known as Rhodophyceae.

5. **Conclusion**: Based on the analysis, the correct answer to the question "Agar agar is obtained from" is **Red Alga (Rhodophyceae)**.

**Final Answer**: Agar agar is obtained from **Red Alga (Rhodophyceae)**.

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