Factor required for erythrocyte stability: March 2010
**Core Concept**
The stability of erythrocytes (red blood cells) is crucial for maintaining proper oxygen delivery to tissues. The correct factor required for erythrocyte stability involves the maintenance of the erythrocyte membrane's structural integrity.
**Why the Correct Answer is Right**
The correct factor required for erythrocyte stability is Spectrin. Spectrin is a protein that forms a network under the erythrocyte membrane, providing mechanical strength and maintaining the cell's shape. This is crucial for preventing hemolysis (red blood cell breakdown) under conditions of shear stress or mechanical deformation. Spectrin works in conjunction with other proteins, such as actin and band 4.1, to form the erythrocyte membrane skeleton.
**Why Each Wrong Option is Incorrect**
**Option A:**
This option would be incorrect as it does not directly relate to erythrocyte stability. While glucose is essential for erythrocyte metabolism, it does not contribute to the structural integrity of the cell membrane.
**Option B:**
This option would be incorrect as it is not directly involved in erythrocyte stability. Although calcium ions can affect erythrocyte function, they do not play a significant role in maintaining the structural integrity of the erythrocyte membrane.
**Option C:**
This option would be incorrect as it is not directly related to erythrocyte stability. While the erythrocyte membrane is rich in cholesterol, the molecule itself does not contribute to the structural stability of the cell.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that Spectrin's role in maintaining erythrocyte stability is critical in conditions such as hereditary spherocytosis, where mutations in the Spectrin gene lead to erythrocyte membrane instability and hemolytic anemia.
**Correct Answer: C. Spectrin**