Which one is the most abundant organic biomolecule in a cell?

Options

A. Water
B. Protein
C. DNA
D. mRNA

Answer

**Step-by-Step Solution:**

1. **Understanding Biomolecules**: Biomolecules are organic molecules that are essential for life. They include proteins, carbohydrates, lipids, and nucleic acids.

2. **Identifying Organic Biomolecules**: Among these, we are focusing specifically on organic biomolecules, which are carbon-based compounds.

3. **Analyzing Cell Composition**: In a cell, various biomolecules are present, but we need to determine which one is the most abundant organic biomolecule.

4. **Considering Proteins**: Proteins play a crucial role in the cell. They are involved in various functions such as structural support (cytoskeleton components like tubulin and actin), catalyzing biochemical reactions (enzymes), and signaling.

5. **Comparing with Other Biomolecules**: While nucleic acids (DNA and RNA) and carbohydrates are also present, they do not match the abundance of proteins in terms of cellular composition.

6. **Conclusion**: Based on the analysis, the most abundant organic biomolecule in a cell is **proteins**.

**Final Answer**: Proteins are the most abundant organic biomolecules in a cell.

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