Calvin used algae in his experiment for tracing out the path of carbon. The algae used were

Options

A. (a) Chlorella and Chlamydomonas
B. (b) Chlorella and Scenedesmus
C. (c) Chlorococcum and Chlorella
D. (d) Chlorococuum and Scenedesmus

Answer

**Step-by-Step Solution:**

1. **Understanding the Experiment**: Melvin Calvin conducted experiments to trace the path of carbon during photosynthesis. He aimed to identify how carbon dioxide is converted into organic compounds in plants.

2. **Selection of Organism**: For his experiments, Calvin chose specific organisms that are capable of photosynthesis. He used unicellular green algae because they are simple and efficient in photosynthesis, making them ideal for tracing carbon pathways.

3. **Identifying the Algae Used**: The specific algae that Calvin used in his experiments were *Chlorella* and *Scenedesmus*. These algae are known for their ability to perform photosynthesis and were suitable for the experiments involving carbon tracing.

4. **Use of Radioactive Carbon**: To trace the path of carbon, Calvin utilized a radioactive isotope of carbon, specifically Carbon-14 (C-14). This allowed him to track the incorporation of carbon into organic molecules during the Calvin cycle.

5. **Conclusion**: Based on the information gathered, the algae used by Melvin Calvin in his experiments were *Chlorella* and *Scenedesmus*. Therefore, the correct answer to the question is option B.

**Final Answer**: The algae used by Calvin were *Chlorella* and *Scenedesmus*.

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