In human respiration, chemical energy is released in the form of ____.

Options

A. Acetyl co-enzyme A
B. ADP
C. `ADPH_(2)`
D. ATP

Answer

**Step-by-Step Solution:**

1. **Understanding Respiration**: Human respiration is a biochemical process that involves the breakdown of complex organic compounds to release energy. This process occurs mainly in the cells and is essential for maintaining life.

2. **Identifying Respiratory Substrates**: The compounds that are oxidized during respiration to release energy are known as respiratory substrates. Common respiratory substrates include carbohydrates, proteins, and fats.

3. **Energy Release Mechanism**: During the breakdown of these substrates, chemical bonds (especially carbon-carbon bonds) are broken, leading to the release of energy. This energy is primarily released in a usable form.

4. **Form of Energy Released**: The energy released during respiration is stored in the form of adenosine triphosphate (ATP). ATP is often referred to as the "energy currency" of the cell because it is used to power various cellular processes.

5. **Conclusion**: Therefore, in human respiration, the chemical energy is released in the form of ATP.

**Final Answer**: In human respiration, chemical energy is released in the form of **ATP**.

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