Lymphatic System Flashcards
Lacteals
Lymphatic Capillaries that transport lipids absorbed from the small intestine into lymphatic vessels and ultimately into the blood.
Lymphocytes
The white blood cells which are involved in the immune response of the animal.
Lymph
A clear watery fluid, similar in composition to plasma, with the important EXCEPTION OF PLASMA PROTEINS, and identical in composition to interstitial fluid.
3 Functions Of Lymphatic System
Tissue Drainage
Absorption In Small Intestine
Immunity
Initial Lymphatics
Small blind-ended terminal lymph vessels which permeate almost every tissue of the body.
3 Factors Contributing To Lymph Flow
Smooth Muscle Layer In Walls Of Lymph Vessels (Lymphatic Pump)
Contraction Of Skeletal Muscles
Pulsation Of Large Arteries
Functions Of Lymph Nodes
Filtering & Phagocytosis (By Macrophages)
Proliferation Of Lymphocytes
B Lymphocytes
Originate In Bone Marrow
Produce proteins called antibodies which destroy the bacteria and inactivate the toxins.
T Lymphocytes
Produced In Bone Marrow & Mature In Thymus
Secrete chemicals that destroy bacteria, poisons, viruses, tumor cells, transplanted cells and cancer cells.
Functions Of The Spleen
Phagocytosis By Macrophages
Storage Of Blood & Platelets
Immune Response (Contains B&T Lymphocytes)
Characteristics Of Thymus Gland
Size & Function Decrease As Animal Ages
Located Near Thoracic Cavity
Produces T Lymphocytes To Kill Invading Organisms
MALT
Mucosa-Associated Lymphoid Tissue (GALT & BALT)
- Found In All Body Systems Exposed To External Environment
- Not Encapsulated
- Contain B&T Lymphocytes
- Lack Afferent Lymph Vessels & Therefore Do Not Filter Lymph
Examples Of MALT
Tonsils - Destroy Swallowed & Inhaled Antigens
Aggregated Lymphoid Follicles (Peyer’s Patches) - Large collections of lymphoid tissue found in small intestine, which intercept swallowed antigens.
