CHapter 23-Lymph Flashcards
function of the lymph system
- produce, maintain, and distribute lymph
- maintain normal blood and interstitial fluid volume
- alternate route for the transport of materials: nutrients, hormones, waste
fluid that lymph vessels transport from tissues to the venous system
lymph
the lymohatic system is made up of?
a system of lymph vessels
location of vessels
most tissues
where are lymph vessels absent in
avascular tissue and CNS
a fluid connective tissue that only occurs within the lymphatic vessels
lymph
where is lymph derived from
interstitual fluid, lymphocytes, macrophages
origin of lymph from
plasma with the interstitual fluid
what is the make up of the plasma that lymph is derived from
water and dissolved materials that leak out of capillaries due to diffusion and filtration
- fluid that lacks proteins and has a lower O2
when is intersitual fluid considered lymph
when it has moved into the lymphatic capillaries
closed end tubes in the interstitual spaces that form networks. made up of a single layer of simple squamous cells with incomplete basal lamina.
-fenestrated
lymphatic capillaries
how do lymphatic capillaries differ from blood capillaries
- larger diameter
- thinner walls
- flat and irregular
- have anchoring filaments that keep the passage open
- overlapping endothelial cells
formation of lymph
- interstitual fluid enters capillaries
- overlapping cells function as one way valves
- moves through fenestrations
- Large things such as viruses and debris follow
merging of lymph capillaries. similar to veins. merge to form trunks. travel with arteries of the same size
medium lymph vessels
tissue make up of medium sized lymphatic vessels
interna
media
adventitia
valves
named for the regions of where they are located. place where medium lymph vessels dump lymph
lymphatic trunks
trunks drain into this. have two– thoracic and right lymphatic. deliver lymph to circulation at subclavians
lymphatic ducts
how does lymph get back into venous circulation
lymphatic ducts– reintroduced to blood stream and becomes part of plasma and is recirculated
thoracic duct that drains lower body; left arm, body, and neck
throacic duct
route of the thoracic duct
- cisterna chyli
through the diaphragm
ascends in front of vetebral column
empties into left subclavian
lymphatic duct that drains the right side of head, neck,, and right arm
right lymphatic duct
route of the right lymphatic duct
starts at right thorax and to the right subclavian vein
special thing about the thoracic ducts
unevenly drains fluid from the body:
- thoracic does the majority
- thoracic is much larger and drains the entire inferior half of the body
movement of lymph– valves
occurs in bulges
prevent backflow
how is lymph moved
with valves– pressure of lymph is less than veins– moved through skeletal muscles and breathing
when drainage of lymph does not occur
lymphedema
primary cells of the lymphoid system. allow for specific immunity or adaptive immunity
lymphocytes
multi-faced immune response to the detection of specific foreign antigens
specific immunity
type of lymphocyte derived directly from bone marrow
- involves NON-SPECIFIC IMMUNITY
- detects chemical signals other than specific antigens and induce apoptosis
NK cells (natural killer cells)
type of lymphocyte that originates and developes in the bone marrow
- stimulated by an antigen to produce antibodies
- can survive for years as a memory cell and become active once exposed to a similar antigen
B cell
type of lymphocyte that originates in the bone marrow but developes in the thymus
- attack cells with antigens indicating viral infection or detrimental mutations
- induce apoptosis
- have memory cells similar to B cells
T cells
reticular connective tissue dominated by lymphocytes. NOT organs, made up of mucosa associate lymphoid tissue. digestive lymph nodules
lymphoid nodules
MALT tissues
tonsils, aggregated lymphoid nodules, and appendix
part of MALT that is positioned around the pharynx. removes pathogens that enter via the air or food. three types: pharyngeal, palatine, lingual
tonsils
MALT tonsils that is located in the nasopharynx– one nodule
pharyngeal tonsil
MALT tonsil located in the soft palate– two nodules
palatine tonsil
MALT tonsil located at the base of the tongue– two nodules
lingual tonsil
part of MALT that lines the mucosa of the small intestines
aggregated lymphoid nodules
part of MALT that bind tubes at the beginning of the large intestines– very prone to infections
appendix
surrounded by a fibrous, connective tissue capsule within the lymphatic system– involve lymph nodes, thymus, spleen
lymphatic organ
bean shaped lymphatic organ that is between several afferent and one efferent vessel. has a hilus
lymph nodes
found within lymph modes. indented region where BVs nerves and efferent lymph vessels connect
hilus
part of lymph nodes– capusle that has trabeculae that subdivide it. has two regions: inner and outer cortex
cortex
regions of the cortex
inner and outer cortex
part of the cortex that consists of aggregated B cells
outer cortex
part of the cortex that allow T cells to enter the blood
inner cortex
part of the cortex of lymph nodes that have B cells leave through the efferent vessel
medulla
found on the left side of the stomach. largest lymphatic organ. contains white and red pulp.
spleen
found in the spleen. resembles lymph nodes
white pulp
found in the spleen. contains large amounts of RBCs. has sinuses, macrophages, T and B cells
red pulp
function of the spleen
remove old RBC store and recycle iron intiate immune response blood resivour RBC production in fetus
in mediastinum.
- first lymph organ to develope– grows until puberty and shrinks with age; replaced with fibrous and adipose tissue
- 2 lobes: cortex and medulla
thymus
part of the thymus– mostly made up of T cells
cortex of thymus
part of the thymus– mostly reticular epithelial cells
medulla of thymus
cortex produces these cells. mature and migrate into medulla. enter blood vessels and go into circulation
T cells of thymus
produce thymosin. promote T cells differentiation
reticular cells of the thymus
