The metal ion which plays an important role in muscle contraction is

Options

A. `Be^(2+)`
B. `Mg^(2+)`
C. `Ca^(2+)`
D. `Ba^(2+)`

Answer

To determine the metal ion that plays an important role in muscle contraction, we can follow these steps:

### Step 1: Understand the Role of Metal Ions in Muscle Contraction
Muscle contraction is a physiological process that requires specific ions to facilitate the interaction between muscle fibers. One of the key ions involved in this process is calcium.

### Step 2: Identify the Relevant Metal Ions
The question provides four options:
- A) Beryllium
- B) Magnesium
- C) Calcium
- D) Barium

### Step 3: Analyze Each Option
- **Beryllium (A)**: While it is a metal, it does not play a significant role in muscle contraction.
- **Magnesium (B)**: Magnesium is important for many biological processes, including muscle function, but it is not the primary ion involved in muscle contraction.
- **Calcium (C)**: Calcium ions (Ca²⁺) are crucial for muscle contraction. They facilitate the interaction between actin and myosin, the proteins responsible for muscle contraction.
- **Barium (D)**: Barium is not involved in muscle contraction and can be toxic in high amounts.

### Step 4: Conclusion
Based on the analysis, the metal ion that plays an important role in muscle contraction is **Calcium (C)**.

### Final Answer
**C) Calcium**

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