Which marine algae produce large amounts of hydroxolloids ( water holding substances ) ?

Options

A. brown and green
B. brown and red
C. green and red
D. only brown

Answer

**Step-by-Step Solution:**

1. **Understanding Hydrocolloids**: Hydrocolloids are water-holding substances that can absorb and retain water. They are important in various applications, including food production and pharmaceuticals.

2. **Identifying Types of Algae**: Algae are classified into three main groups based on their pigment composition:
- **Chlorophyceae**: Green algae
- **Rhodophyceae**: Red algae
- **Pheophyceae**: Brown algae

3. **Recognizing the Algae that Produce Hydrocolloids**: Among these groups, both brown and red algae are known to produce significant amounts of hydrocolloids.

4. **Examples of Hydrocolloids**:
- **Algin**: A hydrocolloid derived from brown algae (Pheophyceae).
- **Carrageenan**: A hydrocolloid derived from red algae (Rhodophyceae).

5. **Conclusion**: Therefore, the marine algae that produce large amounts of hydrocolloids are brown and red algae.

**Final Answer**: Brown and red algae produce large amounts of hydrocolloids.

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