Immune System Functions and Responses

This video tutorial explains the role of T lymphocytes in cell-mediated immunity. It contrasts this with humeral immunity, where antibodies produced by B lymphocytes bind to antigens on pathogens. T lymphocytes, produced in the bone marrow and matured in the thymus, recognize antigens presented on cell surfaces. The video details four scenarios where T lymphocytes recognize antigens and describes the functions of different T lymphocyte types, including T helper cells, cytotoxic T cells, and T regulator cells, which help prevent autoimmune disorders.

What is the primary role of antibodies in the immune system?

• To destroy pathogens directly

• To bind to antigens on pathogens

• To produce antigens

• To migrate to the thymus gland

What triggers the immune system to produce antibodies?

• Recognition of foreign antigens

• Presence of T lymphocytes

• Recognition of self-antigens

• Maturation in the thymus

Where do T lymphocytes mature after being produced in the bone marrow?

• In the thymus gland

• In the liver

• In the lymph nodes

• In the spleen

Which of the following is NOT a situation where T lymphocytes recognize antigens?

• Bacterial infection

• Organ transplant

• Viral infection

• Cancer cell mutation

Which cells act as antigen-presenting cells in the immune response?

• Platelets

• B lymphocytes

• Macrophages

• Red blood cells

What is the function of T helper cells once they are activated?

• To produce antibodies

• To migrate to the bone marrow

• To destroy infected cells directly

• To undergo mitosis and produce clones

What is the main function of interleukins produced by T helper cells?

• To destroy pathogens

• To stimulate phagocytosis

• To migrate to the thymus

• To produce antibodies

Which protein do cytotoxic T cells release to destroy infected cells?

• Antigen

• Cytokine

• Perforin

• Interleukin

What is the role of T memory cells in the immune system?

• To destroy cancer cells

• To regulate immune response

• To remember past infections

• To produce antibodies

How do T regulator cells help prevent autoimmune disorders?

• By increasing phagocytosis

• By producing more T cells

• By down-regulating the immune system

• By attacking self-antigens