lymphatic system

LYMPHATIC SYSTEM
1. Organization and Structure

 The lymphatic system consists of a network of lymphatic vessels and lymph nodes.
 Lymph capillaries are more porous than blood capillaries, allowing interstitial fluid to
enter but preventing backflow due to overlapping cells.

2. Drainage of the Lymphatic System

 Larger lymph vessels converge to form:
o Right lymphatic duct, which drains into the right subclavian vein.
o Thoracic duct, which drains into the left subclavian vein.
 The thoracic duct drains lymph from more than two-thirds of the body’s tissue spaces.

3. Situation of Lymph Vessels

 Present in:
o Deeper layers of skin
o Subcutaneous tissues
o Diaphragm
o Wall of the abdominal cavity
o Omentum
o Linings of respiratory tract (except alveoli)
o Linings of digestive tract
o Linings of urinary tract
o Linings of genital tract
o Liver and heart
 Absent in:
o Superficial layers of skin
o Central nervous system (brain and spinal cord)
o Cornea
o Bones
o Alveoli of lungs




LYMPH NODES
1. Definition and Location

 Small, glandular structures located along lymph vessels.
 Also called lymph glands or lymphatic nodes.
 Common sites: elbow, axilla, knee, groin, abdomen, thorax, neck.