Lymphatic System Flashcards
What is the “lost fluid”
The amount of fluid that enters the interstitial fluid but doesn’t return to the blood. It is cleansed of debris, and pathogens and returned to the systemic circulation
What is the function of the lymphatic vessels?
- return excess tissue fluid to the blood
- return leaked proteins to the blood
- carry pathogens to lymph nodes
- carry absorbed fat from the intestine to the blood through lacteals
What is lymph?
interstitial fluid that enters the lymphatic capillaries
which body region drains lymph into the right lymphatic duct?
right lower limb
- the thoracic duct receives lymph from the right lower limb
- the right lymphatic duct receives lymph from the regions superior to the diaphragm on the right side of the body
what are the primary lymphoid organs?
thymus (thyroid area) and the red bone marrow
what are the secondary primary lymphoid organs?
lymph nodes, tonsils (dimples and chin area), spleen (left side below lungs above intestines), Peyer’s patches (lymphoid nodules in the small intestine), appendix (at the end of the large intestine (right side))
What is the intention of the lymphatic system?
To filter out any bad solutes and molecules that may be within the blood by taking out a bit of fluid from the interstitial fluid and removing waste
What systems does the lymphatic system support?
- cardiovascular
- immune
does the lymphatic system return the interstitial fluid?
YES
What are the 4 main parts of the lymphatic system?
- lymph: watery substance flowing through the lymphatic system, leftover blood plasma forced out of capillaries
- lymphatic vessels: tunnels that get the lymph where it actually needs to be while checking it on the way using |v|
- lymph nodes: checkpoints for the lymph
- lymphatic tissues: some containing immune cells to help cleanse and defend against any potentially harmful substances, others house maturing immune cells
What is the function of the thymus and spleen?
house maturing immune cells aka lymphocytes
What constructs lymphatic capillaries?
endothelial cells and flaplike minivalves that open when pressure outside the capillary is higher than inside
What is the order of travel in the lymphatic system?
lymph node > lymph trunk > lymph duct
increasing in size as they progress
how many lymph ducts are there and where do they feed back?
2 and into lowest pressure areas of the circulatory system
Where does each lymphatic duct collect from?
Right: Upper right torso, right arm, right side of head and thorax dump into the jugular vein
Larger thoracic duct: the rest of the body and dumps into the subclavian vein
What is edema?
Swelling due to buildup of lymph fluid, can result in the blocking of an artery and lack of oxygen
What do lymphocytes in lymph nodes do when they find bacteria or other microorganisms?
- release macrophages that are present in. the lymph node
- activate general immune system if extra support is needed
Where are lymphocytes found and where do they mature?
loose reticular connective tissue
what are inflamed lymph nodes an early sign of?
disease or infection
there are special checkpoints by what other tissues and why?
respiratory and digestive tissues because they are extra sensitive to infections
What are MALTs and what does that stand for?
Mucosa-Associated Lymphoid Tissues the outposts in mucous membranes that help protect extra sensitive tissues
What are examples of MALTs?
Tonsils, Peyer’s patches by the small intestine, appendix
What lymph organ holds a reservoir of platelets?
spleen
what tissue composes the stroma of most lymphoid organs?
reticular connective
what lymphatic vessel collects interstitial fluid?
capillaries
what lymphatic structure absorbs lipids in the intestine?
lacteal
What are the 4 kinds of tonsils and what are their unique functions/locations?
Palatine tonsils are at the back of your throat by the dangly thing/pharynx
Tubal tonsils are located at the sides of the roof of your mouth
Submandibular are sort of at the back of your tongue
Pharyngeal are at the roof of your mouth
What does the lymphatic system help maintain in relation to the cardiovascular system?
blood volume and therefore, pressure
Do lymph nodes have more efferent or afferent vessels?
afferent - slows flow
how many ways does lymph flow and in which direction(s)?
one way, towards the heart
what organ develops and trains lymphocytes?
thymus
what actually filters lymph?
lymph nodes
Excess tissue fluid in the brain drains into the ___
CSF
What is the CSF
Cerebrospinal fluid
What happens when tonsilitis occurs?
inflamed and enlarged tonsils
what is called when lymph nodes are filled with pus?
buboes
what is the name for a severe localized edema?
lymphedema
What is the symptom of lymphangitis?
red lines under the skin that are sensitive to touch
What are the characteristics of lymphatic collecting ducts?
- presence of valves
- anatomical distributions of each vary among individuals
- they’re made of 3 layers of tunics
Why does lymphoid tissue swell when there is an infection?
when there is infection, b lymphocytes divide in order to attack the infection more aggressively, the increased number of cells causes the tissue, and thereby, the organ, to appear swollen
what are the trabeculae extensions of and what is their function?
the capsule of a lymph node, to divide the lymph node into multiple sections
What are the many sections of the lymph node?
what are medullary cords?
thin, inwards extensions from the cortical lymph tissue in the lymph node
what are the different types of tissues in lymph organs
what are the large lymph capillaries in a lymph node that’re created by crisscrossing reticular fibres?
lymph sinuses
which of the following trunks is unpaired? jugular, bronchomediastinal, intestinal, lumbar
the intestinal
what is the site of erythrocyte production in feti?
spleen
define white vs red pulp
Where do B lymphocytes originate and mature?
in red bone marrow
what is the function of T lymphocytes?
producing an immune response
what is the function of b lymphocytes?
producing plasma cells
what is the function of macrophages?
phagocytizing foreign entities
what are dendritic cells and what are their functions?
capture antigens and delivers to lymph nodes while activating t cells
what are reticular cells?
produce reticular fibers called stroma in lymph organs
what is the stroma?
network-like support that acts as scaffolding for immune cells
what is reticular connective tissue?
all lymphoid organs except thymus contain it, the lamina propria of mucous membranes, macrophages in networks, lymphocytes with temporary stopovers
what are the 2 main types of lymphoid tissues?
diffuse lymphoid tissue: which are a loose arrangement of lymphoid cells and some reticular fibers, in basically every organ with larger collections in lamina propria of mucous membranes
lymphoid follicles or nodules: solid, spherical bodies consisting of tightly packed lymphoid cells and reticular fibers with germinal center of proliferating B cells
whats the difference between primary and secondary lymphoid organs?
primary: produce and mature T and B cells
secondary: where mature lymphocytes first encounter antigens and become activated
what is the construction of lymph nodes?
the cortex: follicles with germ centres containing dividing B cells
medulla: has medullary cords containing B and T cells with large lymph sinuses aka lymph capillaries, they also have a large network of reticular fibers where macrophages are stationed to police the lymphatic fluid
enters via afferent vessels on which side?
convex side
