Biology · Human Health and Diseases · NEET
No. This is the most common mistake. NCERT says clearly: the T-cells themselves do NOT secrete antibodies, but they HELP B-cells to produce them. Only B-lymphocytes make antibodies. If a NEET question says T-cells produce antibodies, that statement is WRONG.
B-lymphocytes produce antibodies. NCERT says B-lymphocytes produce 'an army of proteins' called antibodies in response to pathogens, and these go into the blood. T-cells only give help; they do not secrete antibodies.
B-lymphocytes make antibodies and carry out humoral (antibody-mediated) immunity. T-lymphocytes do not make antibodies; they help B-cells and carry out cell-mediated immunity (CMI). Both are types of lymphocytes and both are needed for the full acquired immune response.
Because the antibodies made by B-cells are found in the blood (body fluids). The old word for body fluids is 'humor'. So antibody-mediated immunity is also called humoral immune response. T-cell immunity acts by cells directly, so it is called cell-mediated immunity.
All lymphocytes are first produced in the bone marrow. B-lymphocytes mature in the bone marrow itself. T-lymphocytes leave and mature in the thymus. NEET 2024 confirmed that both bone marrow and thymus provide the micro-environment for the development and maturation of T-lymphocytes.
Both are part of acquired (specific) immunity, not innate immunity. They carry out the primary and secondary immune responses and give memory. Innate immunity uses barriers like skin, phagocytes and natural killer cells instead.
Given below are two statements: Statement I: Bone marrow is the main lymphoid organ where all blood cells including lymphocytes are produced. Statement II: Both Bone marrow and thymus provide micro environments for the development and maturation of T-lymphocytes. In the light of the above statements, choose the most appropriate answer.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
B-lymphocytes make antibodies, and every antibody has four peptide chains: two light (L) and two heavy (H) chains. So an antibody is written as H2L2. T-cells make no antibodies, so H2L2 belongs to B-cell work only.
HIV mainly attacks helper T-lymphocytes (and macrophages). It reduces the number of helper T-cells, so the immune system becomes weak. This is why AIDS lowers immunity.
Yes. Both take part in the primary response (first, weak) and the secondary response (fast, strong). This memory of the first encounter is the basis of acquired immunity and vaccination.
We need both. B-cells give antibody (humoral) protection, mostly against pathogens in blood and fluids. T-cells give cell-mediated protection and also help B-cells work. Together they make the full acquired immune response.
