Lymphocytes that cause the formation of holes in plasma membranes are

Options

A. B cells
B. killer (cytotoxic) T cells
C. suppressor T cells
D. helper T cells

Answer

To answer the question about which lymphocytes cause the formation of holes in plasma membranes, we can break down the information step by step:

### Step-by-Step Solution:

1. **Understanding Lymphocytes**: Lymphocytes are a type of white blood cell that play a crucial role in the immune response. They are primarily divided into B cells and T cells.

2. **Identifying the Type of Lymphocyte**: Among the T cells, there are different types, including Helper T cells and Cytotoxic (Killer) T cells. The question specifically asks about the lymphocytes that create holes in plasma membranes.

3. **Role of Killer T Cells**: Killer T cells, also known as Cytotoxic T lymphocytes (CTLs), are responsible for directly attacking and destroying infected or cancerous cells. They do this by recognizing viral antigens presented on the surface of infected cells.

4. **Mechanism of Action**: When Killer T cells recognize an infected cell, they release proteins called perforins. These perforins insert themselves into the plasma membrane of the target cell, forming pores or holes.

5. **Consequences of Pore Formation**: The formation of these holes disrupts the integrity of the plasma membrane, leading to cell lysis (death) of the infected cell. This is a crucial mechanism for eliminating cells that are compromised by viruses or other pathogens.

6. **Conclusion**: Therefore, the lymphocytes that cause the formation of holes in plasma membranes are the Killer T cells (Cytotoxic T lymphocytes).

### Final Answer:
Killer T cells (Cytotoxic T lymphocytes) are the lymphocytes that cause the formation of holes in plasma membranes.

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