The Lymphatic System and Immunity

Flashcards covering the lymphatic system, its components, and the basics of innate immunity.

Lymphatic System Functions

Draining interstitial fluid, transporting dietary lipids, facilitating immune responses.

Lymphatic System Components

Lymphatic capillaries, vessels, nodes, trunks, ducts, primary and secondary organs.

Lymphatic Capillaries

Have larger pores than blood capillaries, blind ends, and a one-way structure.

Lymph Nodes Function

Encapsulated organs with masses of B and T cells that filter lymph.

Lymph Flow

Interstitial fluid -> lymphatic capillaries -> lymphatic vessels -> lymph nodes -> lymphatic ducts -> subclavian veins.

Primary Lymphoid Organs

Bone marrow and thymus; where immune cells become immunocompetent.

Secondary Lymphoid Organs

Spleen, lymph nodes, and lymphoid tissues; where most immune responses occur.

Lymph Node Afferent Vessels

Vessels through which lymph fluid enters the node.

Lymph Node Efferent Vessels

Vessels that convey lymph, antibodies, and activated T cells out of the node at the hilum.

Thymus Function

T cell maturation.

Spleen

Largest mass of lymphatic tissue; contains white pulp (immune function) and red pulp (blood filtering).

White Pulp

Lymphatic tissue in the spleen where lymphocytes and macrophages carry out immune function.

Red Pulp

Blood-filled venous sinuses in the spleen where platelets are stored and old red cells are destroyed.

Innate Immunity

Immune response present at birth that is non-specific and non-adaptive.

Innate Immunity Barriers

Physical (skin, mucous membranes) and chemical (acidic substances).

Internal Defenses (Innate Immunity)

Phagocytes, NK cells, antimicrobial substances, inflammation, fever.

Fever

Abnormally high body temperature that speeds up body reactions and inhibits some microbes.

Four signs of inflammation

Redness, pain, heat and swelling

Inflammation Function

Disposes of microbes and foreign materials, dilutes toxins, and prepares for healing.

Inflammation Stages

Vasodilation, emigration of phagocytes, and tissue repair.

Vasodilation in Inflammation

Allows more blood to flow to the damaged area, removing toxins and debris.

Chemotaxis

Process that emigration of phagocytes depends on.