When bread is left open in air, certain white and filamentous outgrowth is observed, which makes the bread unsuitable for human consumption. The white filamentous growth is a

Options

A. bacteria
B. fungus
C. protist
D. virus

Answer

**Step-by-Step Solution:**

1. **Observation of Bread**: When bread is left open in the air, a white filamentous growth appears on its surface. This growth is a sign that the bread has become unsuitable for human consumption.

2. **Identification of the Growth**: The white filamentous structure observed on the bread is indicative of fungal growth.

3. **Understanding the Structure**:
- The filamentous structure is known as **mycelium**.
- The individual thread-like structures that make up the mycelium are called **hyphae** (plural of hypha).
- At the tips of these hyphae, there are structures called **sporangia** which contain spores.

4. **Spore Dispersal**: When the sporangia break, they release spores into the air. These spores can land on suitable surfaces (warm and moist) and grow into new fungal colonies.

5. **Conclusion**: The white filamentous growth on the bread is identified as **fungus**. Therefore, the correct answer to the question is that the white filamentous growth is a fungus.

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