LYMPHATIC_ -system LAB

Lymphatic System Overview

• Lymphatic system is a key component of the immune system, aiding in the transport and filtering of lymph.

• Essential for immune surveillance and response.

Components of Lymphatic System

1. Spleen

• Description: Largest lymphoid organ, fist-sized, located on the left side beneath the diaphragm.

• Functions:

  • Site for lymphocyte proliferation and immune response.

  • Cleans blood, removing aged or defective cells and platelets.

  • Stores iron and blood platelets.

• Structures:

  • White Pulp: Lymphocyte-rich area involved in immune function.

  • Red Pulp: Contains blood and disposes of worn-out blood cells.

2. Lymph Nodes

• Description: Principle lymphoid organs located along lymphatic vessels, clustered in areas like the inguinal, axillary, and cervical regions.

• Functions:

  • Filter lymph, with macrophages removing debris.

  • Activate the immune system.

Peyer's Patch

• Clusters of lymphoid follicles in the small intestines.

• Functions:

  • Destroy bacteria, promote long-term immunity through memory lymphocytes.

3. Tonsils

• Description: Simple lymphoid organs forming a ring around the pharynx.

• Types:

  • Palatine Tonsils: Largest, located in the oral cavity; most frequently infected.

  • Lingual Tonsils: Located at the tongue's base.

  • Pharyngeal Tonsils (Adenoids): Located on the posterior wall of the nasal pharynx.

• Function: Trap bacteria for destruction.

4. Thymus

• Description: Bilobed organ located in the neck and thorax; prominent in newborns and decreases in size with age.

• Function: Site for T lymphocyte precursor maturation into immunocompetent lymphocytes.

5. Lacteals

• Description: Specialized lymphatic capillaries in the intestinal villi.

• Function: Absorb digested fats, leading to milky chyle lymph.

Lymphatic Ducts

• Right Lymphatic Duct: Drains lymph from the right upper limb and right side of the head/thorax, empties into the right subclavian vein.

• Thoracic Duct: Larger duct draining the rest of the body, empties into the left subclavian vein.

• Cisterna Chyli: Collects lymph from lower limbs and intestinal trunk.

Histology and Microscopy of Lymphatic Components

• Lymphatic structures like spleen and lymph nodes can be analyzed under a microscope for histological studies.

• Key features: Follicles, germinal centers, and medullary sinuses provide insights into immune cell organization.

Antigens and Antibodies

• Antigen (Ag): Substances recognized as foreign that activate the immune response.

• Antibody: Protein that binds specifically to an antigen; produced by plasma cells derived from B lymphocytes.