Glycolate accumulates in chloroplasts, when there is

Options

A. High `CO_2`
B. Bright light
C. Low temperature
D. Low `CO_2`

Answer

**Step-by-Step Solution:**

1. **Understanding Glycolate Accumulation**: Glycolate is a product of the photorespiration process in plants, particularly in C3 plants where the enzyme ribulose bisphosphate carboxylase/oxygenase (rubisco) plays a crucial role.

2. **Role of Rubisco**: Rubisco can catalyze two different reactions: one with carbon dioxide (CO2) and another with oxygen (O2). When O2 levels are high and CO2 levels are low, rubisco tends to favor the oxygenation reaction, leading to the production of glycolate.

3. **Photorespiration Process**: Photorespiration is considered a wasteful process because it leads to the loss of fixed carbon and the release of CO2. During this process, the first stable compound formed is phosphoglycolic acid, which is then converted into glycolic acid.

4. **Conditions for Glycolate Accumulation**: Glycolate accumulates in chloroplasts primarily under conditions of low CO2 concentration. This is because low CO2 levels increase the likelihood of rubisco engaging in the oxygenation reaction rather than the carboxylation reaction.

5. **Conclusion**: Therefore, glycolate accumulates in chloroplasts when there is low CO2 concentration. This is the correct answer to the question.

**Final Answer**: Glycolate accumulates in chloroplasts when there is low CO2 concentration.

---