Lymphatic and Immune Systems

These flashcards cover key concepts from the lecture on the lymphatic and immune systems, including definitions and functions of important components.

Lymphatic System

A network of vessels that helps maintain fluid balance, protects the body from infection and disease, absorbs dietary lipids, and recovers fluids from tissues.

Lymph

A clear, colorless fluid similar to plasma, but with much less protein, collected from body tissues.

Lymphatic Capillaries

Small, closed-ended vessels that absorb interstitial fluid; allow for the entrance of bacteria and cells.

Immunity

The ability of the body to resist infectious organisms or toxins through specific cellular responses.

Natural Killer (NK) Cells

A type of lymphocyte that plays a role in the innate immune response, destroying compromised host cells.

Phagocytosis

The process by which cells engulf and digest pathogens and debris.

Antigen Presenting Cells (APCs)

Cells that display foreign antigens on their surface; include macrophages, dendritic cells, and B cells.

T Lymphocytes (T Cells)

A type of lymphocyte that matures in the thymus and is involved in the adaptive immune response.

B Lymphocytes (B Cells)

A type of lymphocyte that produces antibodies in response to antigens.

Antibodies

Proteins produced by B cells that specifically bind to antigens to neutralize them or mark them for destruction.

Hypersensitivity

An exaggerated immune response to an antigen that causes tissue damage and inflammation.

Inflammation

A protective response involving increased blood flow, immune cell activity, and tissue repair at sites of injury or infection.

Cytokines

Small proteins released by cells that affect the behavior of other cells, particularly in the immune response.

Complement System

A group of serum proteins that enhance the immune response by promoting inflammation, phagocytosis, and cytolysis.

Memory Cells

Long-lived lymphocytes that provide the body with immunological memory and faster responses upon re-exposure to an antigen.

AIDS

Acquired Immunodeficiency Syndrome, caused by HIV, characterized by a severe reduction in T cells and increased susceptibility to infections.

Autoimmune Diseases

Conditions in which the immune system mistakenly attacks the body's own cells, leading to tissue damage.

Passive Immunity

Immunity acquired through the transfer of antibodies from another individual, either naturally (e.g., breastfeeding) or artificially (e.g., antibody injections).

Active Immunity

Immunity developed through the body’s own immune response to an antigen, either through infection or vaccination.