Lymphatic_system_and_immunity

Lymphatic System

The bodily system responsible for defending the body from environmental hazards and internal threats.

Immunity

The ability to resist infection and disease.

Lymphocytes

White blood cells that are part of the immune response, including B cells, T cells, and natural killer cells.

Innate Immunity

Nonspecific immunity that is present at birth and responds the same way to all types of pathogens.

Adaptive Immunity

Specific immunity developed after exposure to an antigen, involving B and T lymphocytes.

Pathogens

Organisms that cause disease, such as viruses, bacteria, fungi, and parasites.

Lymphatic Vessels

Vessels that carry lymph from peripheral tissues to veins.

Lymph Nodes

Small lymphoid organs that filter lymph before it returns to the venous circulation.

Lymphatic Capillaries

Smallest lymphatic vessels present in almost every tissue of the body, responsible for the absorption of interstitial fluid.

Cytotoxic T Cells

A type of T cell that destroys abnormal cells or infected body cells.

Phagocytes

Cells that attack and engulf microorganisms and debris.

Interferons

Proteins released by lymphocytes and macrophages that trigger the production of antiviral proteins in healthy cells.

Complement System

More than 30 special proteins in plasma that assist antibodies in the destruction of pathogens.

Inflammation

Localized tissue response to injury characterized by redness, swelling, heat, and pain.

Fever

A body temperature greater than normal, often caused by pyrogens, which can inhibit pathogens.

B Cells

Lymphocytes that can differentiate into plasma cells to produce antibodies.

Natural Killer (NK) Cells

A type of lymphocyte that looks for and destroys abnormal cells, including cancer cells.

T Cells

Lymphocytes that are involved in the immune response, including cytotoxic T cells and helper T cells.

Adaptive Defenses

Result from the coordinated activities of lymphocytes and include both cell-mediated and antibody-mediated immunity.

Memory T Cells

A subset of T cells that respond to previously encountered antigens.