In photorespiration, glycine enters from

Options

A. chloroplast to peroxisome
B. peroxisome to mitochondrion
C. mitochondrion to peroxisome
D. chloroplast to mitochondrion.

Answer

To solve the question regarding where glycine enters in photorespiration, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Photorespiration**:
- Photorespiration is a light-dependent process where molecular oxygen is taken up, and carbon dioxide is released from organic compounds.

2. **Identify the Role of Glycine**:
- Glycine is an amino acid that plays a role in the photorespiration pathway. It is produced in the peroxisome during the conversion of phosphoglycolate.

3. **Analyze the Options**:
- **Option A**: Chloroplast to Peroxisome
- Glycine is not present in the chloroplast, so this option is incorrect.
- **Option B**: Peroxisome to Mitochondrion
- Glycine is produced in the peroxisome and then enters the mitochondrion, making this option correct.
- **Option C**: Mitochondrion to Peroxisome
- This option is incorrect because serine, not glycine, moves from the mitochondrion to the peroxisome.
- **Option D**: Chloroplast to Mitochondrion
- Again, since glycine is not present in the chloroplast, this option is also incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer is that glycine enters from the **Peroxisome to Mitochondrion**.

### Final Answer:
**B: From Peroxisome to Mitochondrion**