Agar-agar which is commonly used in microbiological studies and culture media is obtained from

Options

A. Gelidium
B. Laminaria
C. Polysiphonia
D. Batrachospremum

Answer

**Step-by-Step Text Solution:**

1. **Understanding Agar-Agar:**
- Agar-agar is a gelatinous substance that is primarily composed of carbohydrates. It is widely used in microbiological studies and as a culture medium for growing microorganisms.

2. **Source of Agar-Agar:**
- Agar-agar is derived from certain types of seaweed. Specifically, it is extracted from red algae.

3. **Identifying the Correct Seaweed:**
- The question asks from which specific type of seaweed agar-agar is obtained. The main source of agar-agar is a type of red algae known as **Gelidium**.

4. **Evaluating Other Options:**
- The question may provide other options such as Laminaria and Polysiphonia.
- **Laminaria** is a type of brown algae and is primarily known for being a source of iodine, not agar-agar.
- **Polysiphonia** is also a type of red algae but is not the primary source for agar-agar; it is used for other purposes.

5. **Conclusion:**
- After evaluating the options, it is clear that the correct answer is **Gelidium**, as it is the specific red algae from which agar-agar is obtained.

**Final Answer:**
Agar-agar is obtained from **Gelidium**.

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