proteins which present in protoplasm are very Important because

Options

A. they provide definite shape to cell
B. they function as biocatalyst
C. they yield energy
D. they are stored food

Answer

### Step-by-Step Solution:

1. **Understanding Proteins**:
- Proteins are essential macromolecules found in all living cells, including protoplasm. They are composed of amino acids and play various critical roles in biological systems.

2. **Building Blocks of Cells**:
- Proteins serve as the building blocks of cells. They contribute to the structure and function of cells, tissues, and organs.

3. **Biocatalysts**:
- One of the most important functions of proteins is their role as biocatalysts, known as enzymes. Enzymes accelerate biochemical reactions, making them indispensable for metabolic processes.

4. **Metabolism**:
- Proteins are crucial for metabolism, which includes all the chemical reactions that occur within living organisms to maintain life. Without enzymes, these reactions would occur too slowly to sustain life.

5. **Evaluating Other Functions**:
- While proteins can yield energy, they are not the primary source of energy for cells (carbohydrates like glucose are).
- Proteins do not primarily serve as food storage; other macromolecules like polysaccharides fulfill that role.

6. **Conclusion**:
- The most significant reason proteins present in protoplasm are important is that they function as biocatalysts (enzymes) that facilitate metabolic reactions.

### Final Answer:
Proteins present in protoplasm are very important because they function as biocatalysts (enzymes) that catalyze various biological reactions, which are essential for the metabolism of living beings.

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