Test #5: Lymphatic System Flashcards
How many functions of the lymphatic system?
3 functions
What are the 3 functions of the lymphatic system?
- Returns fluids leaked from the vascular system
- Protects the body against foreign matter
- Transports dietary fat
How much fluid is returned from the vascular system every day?
3 liters per 24 hours
What is the response that protects the body against foreign matter?
Immune response
How many parts to the basic anatomy of the lymphatic system?
5 parts
What are the 5 parts to the basic anatomy of the lymphatic system?
- Lymph vessels; 2. Lymph fluid; 3. Lymph cells; 4. Lymph tissue; and 5. Lymph organs
Lymph Vessels
Collect 10% of interstitial fluid left behind venous return.
How many types of lymph vessels?
6 types
What are the 6 types of lymph vessels?
- Lymph capillaries; 2. Lymph collecting vessels; 3. Lymph trunks; 4. Lymph ducts; 5. Cisterna Chyli; and 6. Lacteals
How big are lymph capillaries and where are they located?
a. Smallest of the lymphatic vessels.
b. Present everywhere you have blood capillaries (except the Central Nervous System and bone).
What are lymph capillaries designed to do and how?
a. They are designed to collect excess plasma left behind in the tissue.
b. They collect by hydrostatic pressure.
What is hydrostatic pressure?
The back pressure exerted on a membrane wall by a fluid.
Lymph Collecting Vessels
aka “lymphatics”
a. Lymph capillaries drain into these.
b. They follow alongside veins.
c. They are similar in structure to veins.
d. Many have valves.
Lymph Trunks
a. Lymph collecting vessels drain into these.
b. Lymph trunks drain major regions of the body.
What drains into lymph ducts and how many are there?
a. Lymph trunks drain into lymph ducts.
b. There are only 2.
What are the 2 lymph ducts?
- Right Lymphatic Duct; and 2. Thoracic Duct
What parts of the body drain into the right thoracic duct?
a. Right side of head
b. Right cervical
c. Right thoracic
d. Entire right upper extremity
What parts of the body drain into the thoracic duct?
Drains lymph from everywhere else
a. Left side of head
b. Left cervical
c. Left thoracic and abdomen
d. Entire left upper extremity
e. Pelvis and both lower extremities
Cisterna Chyli
Enlarged region at the proximal thoracic duct that collects lymph from the abdominal, thorax and lower extremities then travels up to the heart.
Where does the right lymphatic duct drain?
The right lymphatic ducts drains into the right subclavian vein -> right brachiocephalic vein -> superior vena cava -> right atrium.
Where does the thoracic duct drain?
The thoracic duct drains into the left subclavian vein -> left brachiocephalic vein -> superior vena cava -> right atrium.
Trace a drop of lymph from the right hallux to the heart.*
Lymph enters the lymph capillaries in the right hallux > drains into the lymph collecting vessels > drains into the lymph trunks > drains into the cisterna chyli > travels up the thoracic duct > drains into the left subclavian vein > drains into left brachiocephalic vein > drains into the superior vena cava > enters the right atrium of the heart.
Trace a drop of lymph from the right index finger (2nd digit) to the heart.*
Lymph enters the lymph capillaries in the right index finger > drains into the lymph collecting vessels > drains into the lymph trunks > drains into the right lymphatic duct > drains into the right subclavian vein > drains into right brachiocephalic vein > drains into the superior vena cava > enters the right atrium of the heart.
Lacteals
Specialized lymph capillaries which drain dietary fat in the small intestine.
Lymph Fluid
Lymph is filtered blood (interstitial fluid) which is collected by lymph capillaries.
Lymph Fluid: Characteristics
a. Clear fluid with dissolved fat and protein.
b. It may contain some waste product, electrolytes and cells (white blood cells).
c. It may have bacteria or viruses.
How many methods of lymph transport?
3 methods
What are the 3 methods of lymph transport?
- Skeletal muscle pump; 2. Respiratory pump; and 3. Contraction of lymph vessels
Lymph Fluid Transport: Skeletal muscle pump
Skeletal muscle contraction puts pressure on the lymph collecting vessels and forces lymph to flow toward the heart.
Lymph Fluid Transport: Respiratory pump
Diaphragm contracts increasing abdominal pressure. This puts pressure on the lymphatic vessels forcing lymph to flow toward the heart.
Lymph Fluid Transport: Contraction of lymph vessels
Large lymph vessels (trunks and ducts) have a thicker smooth muscle layer and can constrict to force lymph flow toward the heart.
How many types of lymph cells?
2 types
What are the 2 types of lymph cells?
- Lymphocytes; and 2. Macrophages
How many types of lymphocytes?
2 types
What are the 2 types of lymphocytes?
- B cells; and 2. T cells
What percentage of lymphocytes are B and T cells respectfully?
B cells - 30%
T cells - 70%
Where are B and T cells born?
They are born in red bone marrow.
Where do B and T cells become immunocompetent?
B cells - red _B_one marrow
T cells - _T_hymus gland
Where are B and T cells found in the body?
B cells - float in the blood and lymph but tend to anchor in lymph tissue (spleen & lymph nodes) to provide “immune surveillance”
T cells - travel in blood and lymph and circulate throughout the body needing to have foreign matter presented to them
What hormone is produced in the Thymus gland?
Thymosin
What is immunocompetence?
B and T cells learn to recognize and fight against foreign matter.
How many methods of lymphocyte mediated immunity?
2 methods
What are the 2 methods of lymphocyte mediated immunity?
- Antibody Mediated Immunity (AMI); and 2. Cell Mediated Immunity (CMI)
What method of lymphocyte mediated immunity do B and T cells fight by?
B cells - Antibody Mediated Immunity (AMI)
T cells - Cell Mediated Immunity (CMI)
Macrophages
a. A type of white blood cell with an insatiable appetite.
b. Phagocytize foreign matter.
c. They can leave the circulatory system.
d. They can act as an Antigen Presenting Cell (APC).
Lymph Tissue
Reticular fibers with lymphocytes and macrophages.