T Cell Activation and Immune Response

The video explains the immune system's defense against pathogens, focusing on the roles of T cells. It distinguishes between innate and adaptive immunity, highlighting how T cells, including cytotoxic and helper types, recognize and respond to antigens. The activation process of T cells involves antigen presenting cells and a two-signal mechanism, ensuring a targeted immune response.

What are the two main components of the immune system?

• Endocrine and nervous systems

• Lymphatic and circulatory systems

• Digestive and respiratory systems

• Innate and adaptive immune systems

Which type of cell is a main component of the adaptive immune system?

• Neurons

• Platelets

• T cells

• Red blood cells

What is the primary function of cytotoxic T cells?

• To produce antibodies

• To destroy infected and cancerous cells

• To transport oxygen

• To digest food particles

Cytotoxic T cells recognize antigens attached to which molecule?

• CD8

• CD4

• MHC class 2

• MHC class 1

Helper T cells are known as CD4+ T cells because of which glycoprotein on their surface?

• CD8

• CD4

• MHC class 1

• MHC class 2

What role do helper T cells play in the immune response?

• They help in the maturation of B cells and activation of other immune cells

• They transport nutrients

• They produce insulin

• They break down toxins

What is the role of antigen-presenting cells in T cell activation?

• They transport oxygen

• They engulf pathogens and present antigens to T cells

• They digest food particles

• They produce antibodies

Which molecule on the surface of the APC binds to CD28 on the T cell during co-stimulation?

• MHC class 1

• MHC class 2

• B7 protein

• CD4

What ensures that T cells are only activated by APCs that have encountered a pathogen?

• Binding of CD28 to B7

• Presence of CD4 glycoproteins

• Production of antibodies

• Secretion of insulin

What happens if there is no binding between CD28 and B7 during T cell activation?

• The T cell produces antibodies

• The T cell undergoes cell death

• The T cell becomes hyperactive

• The T cell transports oxygen