lymphatics

Question 1

functions of lymphatic system

Answer 1

return ISF and leaked plasma proteins back into blood
associated organs provide structural basis of the immune system and house phagocytic cells and lymphocytes

Question 2

primary lymphoid organs

Answer 2

thymus
bone marrow

Question 3

secondary lymphoid organs

Answer 3

spleen
tonsils
lymph nodes
MALT
peyer’s patch
appendix

Question 4

lymph

Answer 4

ISF that enters lymphatics
originates from ISF
responsible for fluid balance, immune response, and transport of nutrients and waste
formed by the filtration of blood plasma through capillaries into the interstitial spaces
followed by the uptake of ISF and other proteins by lymphatic capillaries

Question 5

lymphatic capillaries

Answer 5

similar to blood capillaries
very permeable
form minivalves
anchored via collagen filaments
pathogens travel throughout body via lymphatic capillaries

Question 6

lymphatic collecting vessels

Answer 6

similar to veins
have thinner walls and more valves
vessels in the skin travel w/ superficial veins
deep vessels travel with arteries

Question 7

lymphatic trunks

Answer 7

formed by the union of collecting ducts

Question 8

lymphatic collecting ducts

Answer 8

includes 2 main ducts that lymph is delivered into (right lymphatic duct and thoracic duct)
empties lymph into venous circulation at junction of internal jugular and subclavian veins

Question 9

right lymphatic duct

Answer 9

drains right upper arm and right side of head and thorax

Question 10

thoracic duct

Answer 10

arises as cisterna chyli
drains rest of body

Question 11

lymph nodes

Answer 11

principle lymphoid organ
embedded in clusters along lymphatic vessels
found in inguinal, axillary, and cervical regions of body
filter lymph and activate immune system
contain trabeculae and external fibrous capsule
divided into cortex (dividing B cells) and medulla (macrophages)
contain medullary and lymph sinuses
fewer efferent vessels

Question 12

spleen

Answer 12

largest lymphoid organ
lymphocyte proliferation and immune surveillance and response
cleaneses blood and platelets
removes debris
iron recycling
storage of platelets and monocytes

Question 13

thymus

Answer 13

produces immunocompetent cells
thymic corpuscles involved in regulating T cell development
does not directly fight antigens
teaches lymphocytes to recognize self from non-self antigens

Question 14

tonsils

Answer 14

simpliest lymphoid organ
gather and remove pathogens in food or air
include palatine, lingual, pharyngeal, and tubal tonsils
contains tonsilar crypts, but capsule absent

Question 15

peyer’s patches

Answer 15

clusters of lymphoid follicles
destroy bacteria
found in distal portion of small intestine
generate lymphocytes

Question 16

sentinel lymph nodes

Answer 16

first nodes that receive lymph from suspected cancerous regions
a good indicator of cancer metastasis

Question 17

lymph circulation

Answer 17

convex side via afferent lymphatic vessels->large subscapular sinus and smaller sinuses->medullary sinuses->concave side at hilum via efferent vessels

Question 18

lymphatic trunks

Answer 18

paired lumbar, bronchomediastinal, subclavian, jugular trunk
single intestinal trunk

Question 19

white pulp

Answer 19

around central arteries
mostly lymphocytes in recticular fibers
involved in immune functions

Question 20

red pulp

Answer 20

in venous sinuses and splenic cords
rich in RBCs and macrophages
composed of splenic cords and sinusoids

Question 21

MALT

Answer 21

includes tonsils, peyer’s patches, and appendix
in mucosa of respiratory, and genitourinary organs; rest in digestive tract

Question 22

lymphoid tissue

Answer 22

recticular CT
contain germinal centers (proliferating B cells)

Question 23

lymph transport

Answer 23

milking action of skeletal muscle
pressure changing in thorax during breathing
valves to prevent backflow
pulsations of nearby arteries
contractions of SM in walls of lymphatics

Question 24

lacteals

Answer 24

highly specialized lymphatic capillaries found in the intestinal mucosa

Question 25

trabeculae

Answer 25

divide lymph nodes into compartments

Question 26

lymph sinuses

Answer 26

large lymphatic capillaries spanned by crisscrossing recticular fibers

Question 27

recticular cells

Answer 27

produce fiber stroma of lymphoid organs

Question 28

pathway of lymph

Answer 28

lymph capillaries-> collecting lymph vessels-> lymphatic trunks-> lymphatic ducts

Question 29

dendritic cells

Answer 29

trap antigens and transports them to lymph nodes

Question 30

recticular fibers

Answer 30

found in sinuses of lymph nodes

Question 31

macrophages would most likely be found in this portion of the spleen

Answer 31

splenic cords