Which of the following is not a characteristic of insulin?

Options

A. It stimulates the process of gluconeogenesis.
B. It binds to glycoprotein receptors on cell membrane.
C. Its deficiency leads to diabetes mellitus.
D. Its oversecretion leads to insulin shock.

Explanation

To determine which of the following is not a characteristic of insulin, we will analyze each option provided:

1. **Increases the permeability of cell membrane to glucose**: Insulin facilitates the uptake of glucose by increasing the permeability of the cell membrane to glucose. This statement is true.

2. **Increases the oxidation of glucose in the cells**: Insulin promotes the utilization of glucose for energy by enhancing its oxidation in the cells. This statement is also true.

3. **Initiates the conversion of glycogen to glucose**: This statement is incorrect. Insulin actually promotes the conversion of glucose into glycogen (glycogenesis) for storage, rather than converting glycogen back to glucose (glycogenolysis). Therefore, this is not a characteristic of insulin.

4. **Initiates the formation of hepatic glycogen from excess glucose**: Insulin does promote the conversion of excess glucose into glycogen in the liver (hepatic glycogenesis). This statement is true.

Based on the analysis, the option that is not a characteristic of insulin is:

**Option 3: Initiates the conversion of glycogen to glucose.**