Respiration in yeast

Options

A. takes place in the presence of oxygen
B. yields lactic acid and carbon dioxide
C. in anaerobic and produces carbon dioxide
D. takes place only in darkness

Answer

### Step-by-Step Solution:

1. **Understanding Yeast Respiration**:
- Yeast primarily undergoes a type of respiration known as fermentation, which occurs in the absence of oxygen. This process is termed anaerobic respiration.

2. **Analyzing the Options**:
- **Option 1**: "Takes place in the presence of oxygen."
- This statement is incorrect because yeast respiration occurs anaerobically.

- **Option 2**: "Produces Lactic Acid and Carbon Dioxide."
- This statement is also incorrect. While lactic acid is a product of anaerobic respiration in animals, yeast produces ethanol (alcohol) and carbon dioxide during fermentation.

- **Option 3**: "In anaerobic and produces Carbon Dioxide."
- This statement is correct. Yeast performs anaerobic respiration, producing carbon dioxide and ethanol as byproducts.

- **Option 4**: "In the darkness."
- This statement is misleading. While yeast can ferment in the absence of light, the key factor is the absence of oxygen, not the presence or absence of light.

3. **Conclusion**:
- Based on the analysis of the options, the correct answer is **Option 3**: "In anaerobic and produces Carbon Dioxide."