What are the 2 most important functions of the lymphatic system?
-Maintenance of fluid balance in the internal environment
-immunity
What is the third function of the lymphatic system?
Absorption of lipids from digested food in the intestines and its transport to the systemic veins
*less important function
What do lymphatic vessels do?
Act as drains to collect excess tissue fluid and return it to the venous blood just before it returns to the heart
T/F
Lymphatic vessels that drain peripheral areas of the body parallel the venous return
True
-component of the circulatory system
-consists of moving fluid (lymph) and a group of lymphatic vessels. The vessels drain lymph back into the blood near the heart
Lymphatic system
The lymphatic system contains structures of lymphoid tissue. What are examples of this?
-lymph nodes
-tonsils
-thymus
-spleen
-bone marrow
-small clusters called lymphoid nodules
What does the lymphatic system do?
Transport tissue fluid, proteins, fat and other substances to the general circulation
T/F
Lymphatic vessels begin blindly in the intracellular spaces of the soft tissues; does not form a closed circuit, like the circulatory system
True
T/F
The lymphatic system is not a closed circuit
True
-clear, watery fluid found in the lymphatic vessels
-closely resembles blood plasma in composition but has a lower percentage of protein
Lymph (lymphatic fluid)
T/F lymphatic fluid in the thoracic duct can be higher in protein
True
*collects lymph from majority of the body, including protein rich fluid from the liver and small intestines
-fluid that fills the spaces between the cells and is part of the extracellular matrix
-resembles blood plasma in composition with a lower percentage of protein
-along with blood plasma, constitutes the extracellular fluid
Interstitial fluid
What do interstitial fluid and blood plasma constitute?
Extracellular fluid (outside the cells)
What are the two major drainage pathways for the lymphatic system?
Lymphatic trunks:
-right lymphatic duct
-thoracic duct
-drains the upper right quadrant of the body
-lymph emptied into the right subclavian vein
Right lymphatic duct
-lymph from the rest of the body drains into the thoracic duct, which then drains into the left subclavian vein
Thoracic duct
T/F
The thoracic duct starts as a structure (cisterns chyli) located in the lumbar region of the abdomen
True
*where lymph from the intestines collects - especially fatty lymph (chyle)
What make lymphatic vessels different from veins?
-thinner walls
-have more valves (one way)
-contain lymph nodes
T/F
Lymphatic capillary wall is formed by a single layer of large but very thin and flat endothelial cells
True
*lymphatic vessels contain lymph nodes
-lymphatic capillaries in the villi of the small bowel
-absorb fats and other nutrients from the small intestine
Lacteals
T/F
A high degree of permeability of the capillary wall allows very large molecules and particulate matter to be removed from interstitial spaces
True
What is the function of the lymphatic system?
Helps absorb fats and nutrients during digestion
-in small intestine, lymphatic capillaries are called lacteals
-fats travel through lymphatic system before entering bloodstream
What is the circulation of lymph?
From lymphatic capillaries, lymph flows through progressively larger lymphatic vessels to trunks, then 2 main ducts to reenter blood at the subclavian veins
-right lymphatic duct to the right subclavian vein
-thoracic duct into the left subclavian vein
Where does lymph come from?
-blood capillaries leak plasma into tissues (interstitial fluid) and surrounds cells
-some fluid goes back into blood vessels, but when there’s excess fluid, or pressure builds up, fluid enters lymphatic capillaries(now called lymph)
-lymph travels through vessels, moves through lymph nodes, enters lymphatic ducts, drains into subclavian veins and then into the heart
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Skull - Frontal Bone18
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Skull - Parietal Bones11
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Skull - Occipital11
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Skull - Temporal Bones16
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Skull - Sphenoid Bone4
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Skull - Ethmoid Bone5
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Skull - Orbits8
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Facial Bones - Maxilla15
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Facial Bones - Zygomatic7
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Facial Bones - Palatine7
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Facial Bones - Lacrimal5
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Facial Bones - Nasal8
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Facial Bones - Mandible15
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Sinuses5
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Nervous System Cells46
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Central Nervous System - Part 150
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Central Nervous System - Part 244
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Cardiovascular - Part 152
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Cardiovascular Arteries - Part 115
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Cardiovascular Arteries - Part 216
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Lymphatic System55
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Female Reproductive35
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Male Reproductive28
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Veins38
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Cardiovascular Physiology21
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Peripheral Nervous System37
