Which of the following statements is false ?

Options

A. `Ca^(2+)` ions are important in blood clotting
B. `Ca^(2+)` ions are not important in maintaining the regular beating of the heart
C. `Mg^(2+)` ions are important in the green parts of plants
D. `Mg^(2+)` ions form a complex with ATP

Explanation

To determine which statement is false, we need to analyze each statement one by one.

1. **Statement 1**: "Calcium 2 positive ions are important in blood clotting."
- Calcium ions (Ca²⁺) play a crucial role in the blood clotting process. They are essential for the activation of various clotting factors.
- **Conclusion**: This statement is true.

2. **Statement 2**: "Calcium 2 plus ions are not important in maintaining the regular beating of the heart."
- Calcium ions are vital for the contraction of heart muscles. They help in the electrical signaling that regulates the heartbeat.
- **Conclusion**: This statement is false.

3. **Statement 3**: "Magnesium 2 plus ions are important in the green parts of plants."
- Magnesium ions (Mg²⁺) are indeed essential for chlorophyll, the pigment responsible for the green color in plants and photosynthesis.
- **Conclusion**: This statement is true.

4. **Statement 4**: "Mg2 positive ions form a complex with ATP."
- Magnesium ions bind with ATP (adenosine triphosphate) to stabilize it and make it biologically active.
- **Conclusion**: This statement is true.

After analyzing all statements, we find that the second statement is the only false statement.

**Final Answer**: The false statement is the second one: "Calcium 2 plus ions are not important in maintaining the regular beating of the heart."

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