Tag: cells in immune system

Questions Related to cells in immune system

For a T-cell to recognize an antigen, it must interact with

  1. complement

  2. a macrophage

  3. a B-cell

  4. all of these


Correct Option: B
Explanation:

T cells must be activated by interacting with a professional APC presenting an antigen with their T cell receptor recognizes before they can divide and perform their function. For this, they must interact with a macrophage.

So, the correct option is 'A macrophage'.

Lymphocytes that activate B-cells and T-cells are

  1. macrophages

  2. cytotoxic T-cells

  3. activator B-cells

  4. helper T-cells


Correct Option: D
Explanation:

The three major types of lymphocyte are T cells, B cells and natural killer (NK) cells. Lymphocytes can be identified by their large nucleus. T helper cells(TH cells) assist other white blood cells in immunologic processes, including maturation of B cells into plasma cells and memory B cells and activation of cytotoxic  T cells and macrophages These cells are also known as CD4+ T cells because they express the CD4  glycoprotein on their surfaces. Helper T cells become activated when they are presented with peptide antigens by MHC class two molecules, which are expressed on the surface of antigen- presenting cells (APCs).


So, the correct option is 'Option D'.

Which of the following options is true regarding the B-cells?

  1. They are incapable of leaving lymph tissue to directly confronta foreign antigen

  2. Antibodies produced by B-cells travel in lymph and blood to react with the foreign antigens

  3. Some may develop into plasma cells that secrete antibodies

  4. All of the above


Correct Option: D
Explanation:

B- cells are the bone marrow cells which are the major components of the immune response. B-cells are produced in the bone marrow, they migrate to the spleen and other secondary lymphoid tissues. B-cells are responsible for generating antibodies to different antigens. 

So, the correct option is 'All of the above'.