Question

Both B-cells and T-cells of immune system are produced in
A. Spleen
B. Lymphoid nodes
C. Bone marrow
D. Thymus

Answer 1

Hint: Cell-mediated immunity is mediated by T cells. Antibody-mediated immunity is mediated by B cells, which develop in the bone marrow. When a pathogen is engulfed by an antigen-presenting cell, such as a macrophage, the cell-mediated response begins. T cells are immune cells that specialize in detecting particular foreign particles.

Complete explanation:
Option A: The spleen serves as a blood filter. The spleen detects old or weakened red blood cells and removes them from the body by breaking them down and preserving any valuable materials, such as iron. This keeps the body's blood safe as it circulates.
So, option A is incorrect.
Option B: The collar, armpit, chest, abdominal (belly), and groin are all places where lymph nodes can be found. They produce immune cells that can aid in the battle against infection by targeting and killing germs brought in by lymph fluid. Hundreds of lymph nodes can be found in the body.
So, option B is incorrect.
Option C: Both B and T lymphocytes begin their lives in the bone marrow, but only B lymphocytes mature there; T lymphocytes mature in the thymus. B lymphocytes are named after their origins in the bone marrow, while T lymphocytes are named after their origins in the thymus.
So, option C is correct.
Option D: The thymus is a specialised main lymphoid organ in the immune system. T lymphocytes or thymus cell lymphocytes grow in the thymus. The adaptive immune system, which allows the body to respond to outside invaders, relies heavily on T cells.
So, option D is incorrect

Hence, Option C is the correct answer.

Note:
T cells circulate until they come across their target antigen, rather than attacking all antigens at once. T cells are most often associated with infectious diseases, but they are also used in other forms of adaptive immunity. This involves allergic reactions and tumour responses. They help humans sustain immune homeostasis for decades, but they can also cause inflammatory or autoimmune diseases. T cells’ function changes slightly over the course of a person’s life.