The scientist who was awarded Nobel prize in 1959 for in vitro synthesis of ployribonucleotide :-

Options

A. Mendel
B. Calvin
C. khorana
D. Ochoa

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the scientist who was awarded the Nobel Prize in 1959 for the in vitro synthesis of polyribonucleotide.

2. **Identifying Key Terms**:
- **Polyribonucleotide**: This refers to a polymer made up of ribonucleotide units, which are the building blocks of RNA.
- **In vitro synthesis**: This means the synthesis of compounds outside of a living organism, typically in a controlled laboratory environment.

3. **Reviewing the Options**: The options provided are:
- Mendel
- Kelvin
- Khurana
- Okazaki

4. **Analyzing Each Scientist**:
- **Mendel**: Known as the father of genetics for his work on inheritance patterns in pea plants.
- **Kelvin**: Associated with the Kelvin cycle in photosynthesis, not related to RNA synthesis.
- **Khurana**: Known for demonstrating the role of nucleotides in protein synthesis but not specifically for polyribonucleotide synthesis.
- **Okazaki**: This is likely a misspelling of "Okazaki fragments," which are related to DNA replication, but the correct name here is Severo Ochoa.

5. **Identifying the Correct Scientist**:
- The correct answer is **Severo Ochoa**, who, along with Arthur Kornberg, was awarded the Nobel Prize in Physiology or Medicine in 1959 for their work on the mechanisms of RNA and DNA synthesis.

6. **Final Answer**: The scientist who was awarded the Nobel Prize in 1959 for in vitro synthesis of polyribonucleotide is **Severo Ochoa**.

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