The following vitamin plays a role in transportation of amino acids across the cell membrane.

Options

A. `B_(1)`
B. `B_(2)`
C. `B_(3)`
D. `B_(6)`

Answer

To solve the question regarding which vitamin plays a role in the transportation of amino acids across the cell membrane, we can follow these steps:

### Step 1: Understand the Role of Vitamins
Vitamins are organic compounds that are essential for various biochemical functions in the body. Some vitamins are involved in metabolic processes, including the transportation of nutrients.

### Step 2: Identify the Vitamins Listed
The options provided are:
- B1 (Thiamine)
- B2 (Riboflavin)
- B3 (Niacin)
- B6 (Pyridoxine)

### Step 3: Research the Functions of Each Vitamin
- **Vitamin B1 (Thiamine)**: Primarily involved in carbohydrate metabolism.
- **Vitamin B2 (Riboflavin)**: Important for energy production and the metabolism of fats, drugs, and steroids.
- **Vitamin B3 (Niacin)**: Plays a role in energy metabolism and DNA repair.
- **Vitamin B6 (Pyridoxine)**: Involved in amino acid metabolism, neurotransmitter synthesis, and the formation of myelin.

### Step 4: Focus on Amino Acid Transportation
Among the listed vitamins, Vitamin B6 is known to be crucial in amino acid metabolism. It helps in the conversion of proteins from food into amino acids and is also involved in their transport across cell membranes.

### Step 5: Conclude the Answer
Based on the functions of the vitamins and their roles in amino acid metabolism, the vitamin that plays a significant role in the transportation of amino acids across the cell membrane is **Vitamin B6**.

### Final Answer:
**Vitamin B6**

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