The Lymphatic System (Revision) Flashcards
1
Q
Main Components of the Lymphatic System
A
Lymph
- Formed when Interstitial fluid enters lymphatic capillaries
- Blood plasma forced out of capillaries
- Contains proteins, lipids, and immune cells
Lymphatic Vessels
- Transport lymph throughout the body
- Begin as lymphatic capillaries
- Merge into lymphatic trunks
- Drain into the thoracic duct or right lymphatic duct
Lymph Nodes
- Filter lymph
- Activates lymphocytes
- Has macrophages that engulf pathogens and debris
Lymphoid Organs
- Thymus: Located behind the sternum, site for the maturation of T lymphocytes
- Spleen: Filters blood, removes old red blood cells, site for immune cell activation
- Tonsils: Guard against pathogens entering through the mouth and nose
1
Q
Function of the Lymphatic System
A
Fluid Balance
- Collects excess interstitial fluid
- that leaks from blood capillaries
- returns it to the bloodstream
- Maintains fluid homeostasis
Immune Response
- Facilitates the activation and proliferation of lymphocytes (T cells and B cells)
2
Q
Collecting Ducts of the Lymphatic System
A
Thoracic Duct
- The larger of the two primary collecting ducts
- Drains lymph from most of the body
Right Lymphatic Duct
- Drains lymph from the right side of the head, neck, thorax, and right upper extremity
3
Q
Types of Lymphatic Cells
A
Neutrophils, T Lymphocytes (T cells)
- Involved in adaptive immunity
- Immunological memory
B Lymphocytes (B cells)
- Differentiate into plasma cells
- Produce antibodies
Macrophages
- Phagocytic cells
- Ingest and destroy debris and foreign matter
Dendritic Cells
- Present in lymphatic organs
- Capture and present antigens to T cells
4
Q
Afferent vessels VS Efferent vessels
A
Afferent Vessels
- Transports lymph to lymph nodes
Efferent vessels
- Transports lymph away from lymph nodes
5
Q
Lymphatic Capillaries VS Blood Capillaries
A
Lymphatic Capillaries
- More permeable than blood capillaries
- Can absorb larger molecules
- Eg proteins and lipids
