The site for the production of an enzyme, the deficiency of which causes SCID, in the body is

Options

A. bone marrow.
B. lymphocyte
C. blood plasma.
D. monocytes

Answer

To solve the question regarding the site for the production of an enzyme whose deficiency causes Severe Combined Immunodeficiency (SCID), we can follow these steps:

### Step-by-Step Solution:

1. **Understand SCID**:
- SCID stands for Severe Combined Immunodeficiency, which is a genetic disorder characterized by the disturbed development of functional T cells and B cells caused by numerous genetic mutations.

2. **Identify the Enzyme**:
- The enzyme deficiency that is commonly associated with SCID is adenosine deaminase (ADA). This enzyme is crucial for the proper functioning of the immune system.

3. **Determine the Site of Production**:
- The enzyme adenosine deaminase is produced in lymphocytes, which are a type of white blood cell. Lymphocytes play a vital role in the immune response.

4. **Evaluate the Options**:
- The question presents multiple options for the site of enzyme production.
- **Option 1: Bone Marrow** - While bone marrow is important for producing blood cells, it is not the primary site for the production of ADA.
- **Option 2: Lymphocyte** - This is the correct answer, as lymphocytes are indeed responsible for the production of the enzyme.
- **Option 3: Blood Plasma** - Blood plasma is primarily involved in the transport of nutrients and hormones, not in enzyme production.

5. **Conclusion**:
- Based on the evaluation of the options, the correct answer is **Lymphocyte**, as it is the site for the production of the enzyme whose deficiency leads to SCID.

### Final Answer:
The site for the production of an enzyme, the deficiency of which causes SCID, in the body is **Lymphocyte**.

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