Radioactive isotopes employed to study photosynthesis are

Options

A. `""^(11)C` and `""^(32)P`
B. `""^(15)C` and `""^(32)P`
C. `""^(16)C` and `""^(15)N`
D. `""^(14)C` and `""^(18)O`

Answer

**Step-by-Step Solution:**

1. **Understanding Radioactive Isotopes**:
- Radioactive isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons, leading to different atomic masses. They possess unstable nuclei and emit radiation as they decay.

2. **Identifying Relevant Isotopes**:
- In the context of photosynthesis, two specific radioactive isotopes are commonly used: Carbon-14 (C-14) and Oxygen-18 (O-18).

3. **Carbon-14 in Photosynthesis**:
- Carbon-14 is an isotope of carbon that plants cannot differentiate from the more common Carbon-12. This property allows researchers to trace the incorporation of carbon into organic molecules during photosynthesis. C-14 is particularly valuable for identifying intermediate compounds formed during carbon assimilation.

4. **Oxygen-18 in Photosynthesis**:
- Similarly, Oxygen-18 is an isotope of oxygen that plants also cannot differentiate from the more prevalent Oxygen-16. By using O-18, scientists can track the uptake and release of oxygen during photosynthesis, allowing them to measure the amount of oxygen produced and understand the pathways involved.

5. **Conclusion**:
- The two radioactive isotopes employed to study photosynthesis are Carbon-14 (C-14) and Oxygen-18 (O-18). These isotopes help in understanding the processes of carbon assimilation and oxygen production in plants.

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