LymphaticSystem

Lymphatic System

A network that returns excess interstitial fluid to the bloodstream, consisting of lymphatic vessels, lymph, and lymph nodes.

Lymph

Fluid that is collected from tissues and transported through the lymphatic system.

Lymph nodes

Small, bean-shaped structures that filter lymph and house immune cells, playing a key role in the immune response.

Phagocytic cells

Cells that engulf and destroy pathogens and debris.

T cells (T lymphocytes)

A type of immune cell responsible for managing the immune response and attacking infected cells.

B cells (B lymphocytes)

A type of immune cell that produces plasma cells and antibodies to target antigens.

MALT

Mucosa-associated lymphoid tissue; lymphoid tissues found in mucous membranes that protect against pathogens.

Thymus

An organ where T cells mature, crucial for the immune system, especially during childhood.

Lymphedema

Swelling due to the accumulation of lymph, which can occur if lymphatic vessels are obstructed.

Macrophages

Large immune cells capable of engulfing and digesting cellular debris and pathogens.

Diffuse lymphoid tissue

Loose arrangements of lymphoid cells found in various body organs.

Lymphatic capillaries

Small lymphatic vessels that collect interstitial fluid and are more permeable than blood capillaries.

Appendix

An offshoot of the large intestine containing lymphoid tissue that helps destroy bacteria.

Spleen

A major lymphoid organ that filters blood, removing aged blood cells and storing iron.

Cortex (of a lymph node)

The outer layer of a lymph node that contains lymphoid follicles with B cells.

Medulla (of a lymph node)

The inner region of a lymph node containing B cells, T cells, and macrophages.

Antigens

Substances that the immune system recognizes as foreign, provoking an immune response.

Germinal centers

Areas within lymphoid follicles where B cells rapidly divide and mature.

Vasa vasorum

Small blood vessels that supply larger blood vessels, including those in lymphatic organs.

Lymphatic trunks

Larger lymphatic vessels formed by the convergence of collecting vessels.

Thoracic duct

The main lymphatic duct that drains lymph from most of the body into the blood circulation.

Lymphatic plexus

A network of lymphatic vessels that drain lymph from a specific region or organ.

Chyle

A milky bodily fluid consisting of fat droplets and lymph, formed in the intestines during digestion.

Lymphatic system functions

The mechanisms of the lymphatic system include maintaining fluid balance, filtering pathogens, and facilitating fat absorption.

Primary lymphoid organs

Organs such as the bone marrow and thymus where lymphocytes are formed and mature.

Secondary lymphoid organs

Organs such as lymph nodes and the spleen where lymphocytes are activated and immune responses occur.

Cisternae chyli

A dilated sac at the lower end of the thoracic duct that collects lymph before it enters the thoracic duct.

Immunological memory

The ability of the immune system to respond more effectively to pathogens that have been encountered previously.

Lymphatic drainage

The process by which excess interstitial fluid is collected and transported through lymphatic vessels.

Natural Killer (NK) cells

A type of lymphocyte that can destroy tumor cells and virus-infected cells without prior sensitization.

Antigens presenting cells (APCs)

Cells that display antigens on their surface and help activate T cells

Lymphatic system role in immunity

The lymphatic system helps facilitate the immune response by transporting immune cells and filtering pathogens.

Role of memory B cells

Memory B cells are long-lived cells that provide a quicker and more effective response to previously encountered antigens.

Role of dendritic cells

Dendritic cells are antigen-presenting cells that capture and process antigens to activate T cells.

Hematopoiesis

The process of forming blood cells, including lymphocytes, which occurs primarily in the bone marrow.

Lymph fluid composition

Lymph fluid contains water, proteins, electrolytes, and cells, mainly lymphocytes, that help in immune responses.

Swollen lymph nodes

An indication of infection or disease; they become enlarged as they produce more immune cells to fight pathogens.

Anatomy of lymph nodes

Lymph nodes are surrounded by a fibrous capsule and contain a cortex and medulla, which house different immune cells.

Spleen functions

The spleen filters blood, recycles iron, and produces lymphocytes, playing a critical role in immune surveillance.