Which one contains alginic acid

Options

A. Diatoms
B. Blue green algae
C. Laminaria
D. Yellow green algae.

Answer

**Step-by-Step Solution:**

1. **Understanding Alginic Acid**: Alginic acid, also known as algin, is a polysaccharide that is primarily found in the cell walls of certain types of algae. It is important to identify which type of algae contains this substance.

2. **Identifying Types of Algae**: The question provides four options:
- a. Diatoms
- b. Blue-green algae
- c. Laminaria
- d. Yellow-green algae

3. **Analyzing Each Option**:
- **Diatoms**: These are a type of microalgae that belong to the group of organisms known as Bacillariophyta. They do not contain alginic acid.
- **Blue-green algae**: Also known as cyanobacteria, these are prokaryotic organisms and do not contain alginic acid.
- **Laminaria**: This is a genus of brown algae (Phaeophyceae) that is known to contain alginic acid in its cell walls.
- **Yellow-green algae**: These are a group of algae that do not contain alginic acid.

4. **Conclusion**: Based on the analysis, the only option that contains alginic acid is **c. Laminaria**.

5. **Final Answer**: The correct answer is **c. Laminaria**.

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