Which technique has helped in inverstigation of calvin cycle ?

Options

A. X-Ray cyrstallography
B. X-Ray technique
C. Radioactive isotope (autoradiography) technique
D. Intermittent light

Answer

**Step-by-Step Solution:**

1. **Understanding the Calvin Cycle**: The Calvin cycle is a crucial part of photosynthesis that occurs in the stroma of chloroplasts. It is responsible for converting carbon dioxide and other compounds into glucose.

2. **Identifying the Techniques**: The question asks about the techniques used to investigate the Calvin cycle. Several options are provided: X-ray crystallography, X-ray technique, radioactive isotope, autoradiography technique, and intermittent light.

3. **Historical Context**: The Calvin cycle was discovered by scientists named Calvin, Benson, and Bassham. Their research focused on understanding how carbon dioxide is fixed during photosynthesis.

4. **Use of Radioactive Isotopes**: The key technique that helped in the investigation of the Calvin cycle was the use of radioactive isotopes, specifically Carbon-14 (C-14). This isotope was introduced into the plants in the form of carbon dioxide (CO2).

5. **Tracing the Path**: By using C-14, the scientists were able to trace the path of carbon through the Calvin cycle. They observed how CO2 was converted into glucose, which is the primary product of the cycle.

6. **Conclusion**: Based on the investigation methods used by Calvin, Benson, and Bassham, the correct answer to the question is the use of radioactive isotopes, specifically C-14, and the technique of autoradiography to trace the path of the isotope.

**Final Answer**: The technique that has helped in the investigation of the Calvin cycle is the use of radioactive isotopes (C-14) and autoradiography.

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