Hybridoma cells are

Options

A. only cells having oncogenes
B. product of spore formation in bacteria
C. nervous cells of frog
D. hybrid cells resulting from myeloma cells.

Answer

### Step-by-Step Solution:

1. **Definition of Hybridoma Cells**: Hybridoma cells are a type of cell that is formed by the fusion of two different types of cells: B-cells and myeloma cells.

2. **Role of B-cells**: B-cells are a type of white blood cell that produces antibodies in response to antigens (foreign particles). They play a crucial role in the immune response.

3. **Role of Myeloma Cells**: Myeloma cells are cancerous cells that have lost the normal control over their cell division, leading to rapid and uncontrolled growth. They are essentially tumor cells.

4. **Fusion of Cells**: The fusion of B-cells and myeloma cells results in hybridoma cells. This process combines the antibody-producing capability of B-cells with the rapid division characteristic of myeloma cells.

5. **Purpose of Hybridoma Technology**: The primary purpose of creating hybridoma cells is to produce monoclonal antibodies in large quantities. Monoclonal antibodies are identical antibodies that are produced by the hybridoma cells and can be used for various medical and research applications.

6. **Incorrect Options**:
- The first option incorrectly states that hybridoma cells have oncogenes exclusively, which is not true since proto-oncogenes are present in all cells.
- The second option incorrectly associates hybridoma cells with bacterial spore formation, which is not relevant.
- The third option refers to frog nervous cells, which are not related to hybridoma cells.

7. **Correct Option**: The most appropriate answer regarding hybridoma cells is that they are formed from the fusion of myeloma cells and B-cells, making option D the correct choice.