In a living system, the chemical energy is principally stored in the form of

Options

A. Nucleotide diphosphates
B. Nucleoside triphosphates
C. Nucleotide triphosphates
D. Nucleoside diphosphates.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the form in which chemical energy is principally stored in a living system.

2. **Understanding Chemical Energy Storage**: In biological systems, energy is stored in various forms, but we need to pinpoint the principal form.

3. **Recognize ATP as the Key Molecule**: The primary molecule responsible for storing and transferring energy in cells is Adenosine Triphosphate (ATP).

4. **Define ATP**: ATP is a nucleotide that consists of:
- A nitrogenous base (adenine)
- A pentose sugar (ribose)
- Three phosphate groups

5. **Explain the Role of ATP**: ATP is often referred to as the "energy currency" of the cell because it is used to power various cellular processes.

6. **Conclusion**: Therefore, in a living system, the chemical energy is principally stored in the form of ATP (Adenosine Triphosphate).

**Final Answer**: In a living system, the chemical energy is principally stored in the form of ATP (Adenosine Triphosphate).

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