blood and lymph- lymph system (part 2) Flashcards
what is a lymph
drains excess interstitial fluid from tissues
what is lymph made of
clear watery and slightly yellow
made of tissue fluid, plasma proteins, bacteria, cellular debris and lymphocytes
similar in comparison to blood plasma
no rbc
functions of the lymphoid system
- drain excess interstitial fluid from tissues
- immune response
- transport of dietary lipids
what makes up lymphoid system
- lymph vessels
- lymph nodes
- red bone marrow
- thymus
- tonsils
- spleen
where does lymph flows
lymphatic capillaries
lymph vessels
lymph trunks (via lymph nodes)
lymphatic ducts
venous blood
lymphatic capillaries s
- closed at one end
- one cell thick
- overlapping cells form one way entrance
- greater permeability and larger diameter than blood capillaries
lymphatic vessels
- capillaries join together to form vessels
- contains valves
- similar to veins (thin walls)
- flow thru lymph nodes
- present where there’s blood capillaries = except for teeth, bone marrow, CNS and avascular tissue
lymph nodes
- over 600 nodes are costed along vessels
- usually occur in groups
- lymph will pass thru 8-10 nodes before returning to blood
major groups of lymph nodes
- cervical nodes (along internal jugular vein)
- axillary nodes ( in axilla)
- deep nodes (related to aorta and celiac trunk and sup and inf mesentric arteries)
- pericranial ring (base of head )
- tracheal nodes (related to trachea and bronchi)
- inguinal nodes (along inguinal ligament)
- femoral nodes (along femoral vein)
lymphatic trunks
vessels unite to form trunks
intestinal trunk
l and r lumbar trunks
l and r bronchomediastinal trunks
l and r subclavian trunks
l and r jugular trunks
intestinal trunk
drain lymph from:
stomach
spleen
pancreas
intestine
part of liver
lumbar trunks
drain lymph from;
lower limbs
pelvis
kidney
adrenal gland
abdominal wall
bronchomediastinal trunk
drain lymph from:
thoracic wall
heart
lungs
subclavian trunks
drain lymph from:
- upper limbs
jugular trunks
drain lymph from:
head
neck
lymphatic duct
trunks unite to from 2 ducts:
thoracic (left) and right lymphatic
drain into venous system
thoracic duct
receives lymph from:
intestinal trunk
l + r lumbar
l bronchomediastinal
l subclavian
l jugular
drains venous blood:
into left subclavian vein at junction with left internal jugular
right lymphatic duct
receives lymph from:
right jugular
right subclavian
right bronchomediastinal
drain into venous blood:
junction of right internal jugular and right subclavian
how is movement aided in lymphatic flow
- smooth muscle in walls of large lymph vessels
- pulsing of arteries
- skeletal muscle contraction
- pressure changes in respiration
valves= no back flow
lymphoid organs and tissues
primary lymphatic organs/ tissue:
sites where lymphocytes are produced, marie and become capable of immune response
- red bone marrow= site of T and B cell production and B cell maturation
- thymus= site of T cell maturation
secondary lymphatic organs/tissues:
items where most immune responses cut or develop
- lymph nodes
- spleen
- tonsils
- lymph nodules
thymus
structure and location:
- 2 lobes with fibrous connective tissue capsule
- extends from superior to the anterior mediastinum
- lies between sternum and great vessels
- maximum size at puberty
function:
- maturation of T lymphocytes
lymph nodes
filters and phagocytes foreign material
maturation and proliferation of lymphocytes
mucosa associated lymphoid tissue
uncapsulated collections of lymphoid tissue
contain B and T cells
don’t filter lymph
found in:
- gastrointestinal tract
- respiratory tract
- genitourinary tract
example of MALT
tonsils= trap pathogens from food or inhaled air
spleen loc and str
location: left hypochondriac region of abdominal cavity between fungus (upper portion) of stomach and diaphragm
structure: 12cm long and 7cm wide
made up: outer capsule and stroma
parenchyma: white pulp (lymphatic tissue) and red pulp (venous sinuses)
spleen function
white pulp: lymphatic tissue
lymphocytes (immune response)
macrophages (phagocytosis)
filters BLOOD NOT LYMPH
red pulp: blood filled venous sinuses
- destruction of old rbc
- stores of blood and platelets
- produces rbc in foetus
