One-gene-one enzyme hypothesis was proposed by :-

Options

A. R. Franklin
B. Hershey and Chase
C. A.Garrod
D. Beadle and Tatum

Answer

To solve the question "One-gene-one enzyme hypothesis was proposed by:", we can follow these steps:

### Step 1: Identify the Options
The options provided are:
- R Franklin
- Hershey and Chase
- A Garraud
- Beadle and Tatum

### Step 2: Recall the One-Gene-One-Enzyme Hypothesis
The one-gene-one enzyme hypothesis is a concept in genetics that suggests that each gene is responsible for the production of a single enzyme, which in turn controls a specific metabolic pathway.

### Step 3: Research the Scientists
Among the options, we need to identify which pair of scientists proposed this hypothesis. The correct pair is George Beadle and Edward Tatum.

### Step 4: Confirm the Year of Proposal
The one-gene-one enzyme hypothesis was proposed by Beadle and Tatum in 1948. This information is crucial for confirming the accuracy of the hypothesis and its proponents.

### Step 5: Recognize the Impact of the Hypothesis
This hypothesis was significant as it laid the foundation for biochemical genetics, establishing that genes are chemical substances that can produce enzymes. Beadle and Tatum were awarded the Nobel Prize in 1958 for their work.

### Conclusion
The correct answer to the question is **Beadle and Tatum**.

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