Which one is absent in erythrocytes ?

Options

A. Krebs' cycle
B. Enzymes
C. EMP pathway
D. Hyaloplasm

Explanation

**Step-by-Step Solution:**

1. **Understanding Erythrocytes**: Erythrocytes, commonly known as red blood cells (RBCs), are specialized cells responsible for transporting oxygen throughout the body. They have a unique structure and function that distinguishes them from other cell types.

2. **Analyzing the Options**:
- **Option A: Kreb Cycle**: The Kreb cycle (also known as the citric acid cycle) occurs in the mitochondria of cells. Since erythrocytes lack mitochondria, they cannot perform the Kreb cycle.
- **Option B: Enzymes**: Erythrocytes do contain various enzymes, such as ATPase, which are essential for their metabolic functions.
- **Option C: EMP Pathway**: The Embden-Meyerhof-Parnas (EMP) pathway is a glycolytic pathway that erythrocytes utilize to convert glucose into ATP, indicating that this pathway is present in them.
- **Option D: Hyaloplasm**: Hyaloplasm is the fluid component of the cytoplasm, which is present in all cells, including erythrocytes.

3. **Conclusion**: Based on the analysis, the Kreb cycle is the only option that is absent in erythrocytes due to their lack of mitochondria. Therefore, the correct answer is **Option A: Kreb Cycle**.

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