Lecture 15 Flashcards
The Lymphatic System helps to maintain the body’s fluid environment by _____ and _____ lymph from ____ back into the ___________
filtering; draining; tissues; bloodstream
The lymphatic system includes what structures (3)
- Lymphatic Vessels
- Lymph Nodes
- Several Organs
What is Lymph?
Interstitial fluid that has leaked out of blood capillaries, containing white blood cells (that have been absorbed by lymphatic capillaries)
What are Lymph Nodes?
small bean shaped structures where lymph is filtered
How do Lymph Nodes filter Lymph?
They trap foreign substances (bacteria, viruses) which then get destroyed by the immune cells present w/in the LN
What are the Lymph Organs? (3)
- Spleen
- Thymus
- Red Bone Marrow
What are the Primary Lymph Organs? (2)
Red Bone Marrow & Thymus
What are the Secondary Lymph Organs? (3)
- Lymph Nodes
- Spleen
- Lymphatic Nodules
Describe the general functions of Primary and Secondary Lymph organs.
Primary: these organs produce and mature immune cells
Secondary: where immune response is most active
What are Immunocompetent cells? What are the 2 groups?
Cells that are able to recognize and respond to antigens
- B lymphocytes
- T lymphocytes
What is Lymphatic Flow?
Them movement of lymph through the lymphatic system; from lymphatic capillaries through lymph nodes, into larger vessels and ducts; then draining into the venous system
Describe the presentation of Antigens.
Dendritic Cells capture Antigens and present them to T cells; initiating the immune response
Differentiate between B cells and T cells
B cells: manufactured in the bone marrow - involved in producing antibodies
T cells: manufactured in the thymus - involved in the cell mediated immune responses
What are the roles of the Spleen and the Thymus in the immune system?
Spleen: filters blood (removing old RBC and pathogens), produces antibodies & activates immune response
Thymus: where T cells are produced, mature, and become immunocompetent
Lymphatic capillaries are found throughout the body, except in…
Avascular Tissue
What are Anchoring Filaments?
The structures that help to hold capillaries in place, and react to changes in tissue pressure
When there’s swelling, what happens with the anchoring filaments?
The filaments pull on overlapping endothelial cells, which allows for more fluid to enter the lymphatic capillary
What are Lacteals?
specialized lymphatic capillaries in the small intestine that contains chyle (dietary lipids)
Lymphatic Capillaries merge to form…
Lymphatic Vessels
At intervals along the vessels, fluid flows through…
Lymph Nodes
What are the 5 major drainage trunks?
- Lumbar Trunks
- Intestinal Trunks
- Bronchomediastinal Trunks
- Subclavian Trunks
- Jugular Trunks
List the order of Lymph Flow including entrance.
- Plasma enters venous blood
- Lymphatic Capillaries
- Lymphatic Vessels
- Lymph Nodes
- Venous Blood
- Lymph Ducts
- Lymph Trunks
What is the function of the 5 major trunks?
Drainage
What do the Lumbar Trunks drain?
The Lower Extremities, Pelvis, Visceral Wall, Abdominal Wall, Kidneys
What do the Intestinal Trunks drain?
The Stomach, Intestines, Spleen, Pancreas, Liver
What do the Bronchomediastinal Trunks drain?
Lungs, Heart, Thoracic wall
What do the Subclavian Trunks drain?
Upper Extremities (arms)
What do the Jugular Trunks drain?
Head and Neck
What do Lymph Ducts do?
Returns lymph back to the circulatory system
Lymph ducts return lymph back to the circulatory system via what?
the Venous System
Trunks on which side of the body all have independent entries?
the Right Side
Which Lymphatic Duct is the main duct, and is responsible for draining both lower limbs as well left side of head, neck and chest?
Thoracic Lymphatic Duct (aka Left LD)
What is the Right Lymphatic Duct responsible for draining?
The right side of the Head, Neck, and Chest - and the Right Arm
What is the Left Lymphatic Duct / Thoracic LD responsible for draining?
the Lower Limbs, the left side of the Head, Neck, and Chest