Choose the false statement about T cytotoxic cells.
a. They stimulate B cells
b. They destroy virus-infected cells
c. They destroy cancer cells
d. They are activated by MHC I bound to antigens on APCs
e. They mediate the cellular branch of adaptive immunity

Verified step by step guidance

Step 1: Understand the role of T cytotoxic cells (also called CD8+ T cells) in the immune system. They are primarily responsible for killing infected or abnormal cells, such as virus-infected cells and cancer cells.

Step 2: Review each statement carefully: (a) 'They stimulate B cells' - consider which T cell subset is mainly responsible for helping B cells (hint: T helper cells, not cytotoxic T cells).

Step 3: Analyze statement (b) 'They destroy virus-infected cells' - this is a known function of cytotoxic T cells, so this statement is true.

Step 4: Analyze statement (c) 'They destroy cancer cells' - cytotoxic T cells can recognize and kill cancerous cells, so this is true.

Step 5: Analyze statements (d) and (e): Cytotoxic T cells are activated by antigens presented on MHC class I molecules on antigen-presenting cells (APCs), and they mediate the cellular branch of adaptive immunity, so both are true.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Video duration:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Function of T Cytotoxic Cells

T cytotoxic cells (CD8+ T cells) are immune cells that directly kill virus-infected cells and cancer cells by recognizing antigens presented on MHC I molecules. They play a critical role in eliminating intracellular pathogens and abnormal cells.

Activation of T Cytotoxic Cells

T cytotoxic cells are activated when their T-cell receptors recognize antigen peptides presented by MHC I molecules on antigen-presenting cells (APCs). This activation triggers their proliferation and cytotoxic functions.

Role of T Cytotoxic Cells in Adaptive Immunity

T cytotoxic cells mediate the cellular branch of adaptive immunity by directly killing target cells, unlike B cells which mediate humoral immunity by producing antibodies. They do not stimulate B cells; that role is primarily for helper T cells.

Recommended video:

Guided course