Chapter 21 - Immune System

This set of flashcards covers key concepts related to the immune system, including innate and adaptive defenses, types of immune cells, and the role of antibodies.

What are the two main types of immune defenses?

Innate defenses and adaptive defenses.

What are the surface barriers in the innate immune system?

Skin and mucous membranes.

What is the function of phagocytes in the immune system?

They engulf and destroy pathogens that breach surface barriers.

What do natural killer (NK) cells do?

They promote apoptosis of virus-infected or cancerous cells.

What is inflammation's role in the immune response?

It prevents injurious agents from spreading and promotes tissue repair.

What do antimicrobial proteins do?

They protect uninfected cells from viral takeover and enhance immune responses.

What is the primary response of B lymphocytes?

Humoral immunity, primarily targeting extracellular pathogens.

Where do T lymphocytes mature?

In the thymus.

What is the role of helper T cells in the immune response?

They coordinate both humoral and cellular immunity.

What occurs during the apoptosis of a T cell?

It is a programmed cell death that eliminates self-reactive T cells.

What is the role of antibodies in the immune system?

They neutralize pathogens and signal other immune cells.

What is the difference between active and passive humoral immunity?

Active immunity is generated by exposure to an antigen; passive immunity is provided through antibodies from another source.

What are complement proteins involved in?

Enhancing inflammation, opsonization, and lysing target cells.

What is the function of vasodilation during inflammation?

It increases blood flow to the affected area.

What triggers the activation of T cells?

Recognition of antigens presented by major histocompatibility complex (MHC) proteins.