`alpha`-cells of pancreas are destroyed. The process affected is

Options

A. Glycogenolysis
B. Glycogenesis
C. Proteolysis
D. Cytolysis.

Answer

### Step-by-Step Solution:

1. **Understanding Alpha Cells**: Alpha cells are located in the islets of Langerhans in the pancreas. They are responsible for producing the hormone glucagon.

2. **Role of Glucagon**: Glucagon plays a crucial role in regulating blood sugar levels. Its primary function is to increase blood glucose levels by stimulating the liver to convert stored glycogen into glucose, a process known as glycogenolysis.

3. **Impact of Alpha Cell Destruction**: If the alpha cells are destroyed, they will no longer be able to produce glucagon. This absence of glucagon will directly affect the process of glycogenolysis since glucagon is the hormone that initiates this process.

4. **Analysis of Options**:
- **Glycogenolysis**: This is the breakdown of glycogen into glucose, stimulated by glucagon. If alpha cells are destroyed, glucagon secretion is halted, thus glycogenolysis is affected.
- **Glycogenesis**: This is the synthesis of glycogen from glucose. It does not require alpha cells, as it is primarily regulated by insulin from beta cells.
- **Proteolysis**: This refers to the breakdown of proteins. Alpha cells do not play a role in this process.
- **Cytolysis**: This is the bursting of cells due to osmotic imbalance and is not related to the function of alpha cells.

5. **Conclusion**: Since the destruction of alpha cells leads to a lack of glucagon, the process that will be affected is **glycogenolysis**.

### Final Answer:
The process affected by the destruction of alpha cells in the pancreas is **glycogenolysis**.

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