Mammals born without a thymus gland fail to manufacture :-

Options

A. B -Lymphocytes
B. T -Lymphocytes
C. Plasma cells
D. Basophils

Answer

To solve the question "Mammals born without a thymus gland fail to manufacture:", we need to understand the role of the thymus gland in the immune system. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the function of the thymus gland
The thymus gland is a crucial organ in the immune system, primarily involved in the development and maturation of T-lymphocytes (T-cells), which are essential for cell-mediated immunity.

**Hint:** The thymus gland is vital for T-cell development.

### Step 2: Identify the hormones secreted by the thymus gland
The thymus gland secretes thymosins, which are peptide hormones that promote the differentiation and maturation of T-lymphocytes from precursor cells.

**Hint:** Thymosins are key hormones produced by the thymus.

### Step 3: Recognize the consequences of thymus gland absence
If mammals are born without a thymus gland, they will not be able to produce thymosins. This lack of thymosins means that T-lymphocytes cannot differentiate properly, leading to a deficiency in these immune cells.

**Hint:** Absence of thymosins affects T-lymphocyte production.

### Step 4: Analyze the options provided
The question lists several cell types: B-lymphocytes, T-lymphocytes, plasma cells, and basophils. Since the thymus is specifically responsible for T-lymphocyte development, the absence of the thymus will directly impact the production of T-lymphocytes.

**Hint:** Focus on which cells are directly affected by the thymus gland.

### Step 5: Conclude the answer
Mammals born without a thymus gland will fail to manufacture T-lymphocytes, as these cells are dependent on the thymus for their development.

**Final Answer:** T-lymphocytes.