Spirogyra is called pond silk because

Options

A. Filaments are made up of silk
B. Filaments are slippery to touch
C. Both A and B
D. None of the above.

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: Spirogyra is a type of green algae.
- **Hint**: Remember that Spirogyra belongs to the group of organisms known as algae.

2. **Understand Its Habitat**: Spirogyra is commonly found in freshwater environments, particularly in stagnant water bodies.
- **Hint**: Think about where you might find algae growing in nature.

3. **Examine Its Structure**: Spirogyra has long, filamentous structures. These filaments are characteristic of its morphology.
- **Hint**: Visualize the structure of Spirogyra and how its long filaments might appear in water.

4. **Analyze the Filaments**: The filaments of Spirogyra are covered by a mucilaginous sheath, which contributes to its texture.
- **Hint**: Consider what a "mucilaginous sheath" might feel like and how it affects the organism.

5. **Identify the Composition of the Sheath**: The slippery nature of the sheath is due to the presence of pectin, a polysaccharide.
- **Hint**: Recall what pectin is and its common uses in food products.

6. **Conclude the Reason for the Name**: Because the filaments are slippery to touch due to the mucilaginous sheath, Spirogyra is referred to as "pond silk."
- **Hint**: Think about why something that feels silky might be given that name.

**Final Answer**: Spirogyra is called pond silk because its filaments are slippery to touch due to the presence of a mucilaginous sheath containing pectin.

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