arteries
strong thick walled carrying blood away from the heart and under high pressure
arteries subdivide into…
arterioles
arterioles
carry blood to capillaries (gas and nutrient exchange)
arterial wall layers?
tunica intima, tunica media, and tunica externa
tunica interna/intima
is simple squamous epithelium
tunica media
middle smooth muscle layer w/ collagen and in some cases elastic fibers
tunica externa
is the thin outer layer of the vessels
the tunica externa is made of?
loose areolar connective tissue
elastic arteries is also called
conducting arteries
the largest artery?
elastic arteries
what is the elastic arteries?
-large amount of elastic fibers in thick tunica media; larger diameter size.
-examples include, aorta, pulmonary trunk, common iliac arteries
muscular arteries size?
medium
muscular arteries aka
distributing arteries
what is muscular arteries?
-has thick media w smaller diameter
-capable of greater vasoconstriction and vasodilation to adjust blood flow
-distribute blood to various organs
anastamoses
-union of the branches of two or more arteries supplying the same body region
-provide alternate routes, for blood to reach organs due to blockage
-collateral circulation
-occur between arterioles and venules
vasoconstriction
increase resistance and increase blood pressure
vasodialtion
decrease resistance and decreases blood flow
capillaries
have a walls of simple squamous epithelium
capillaires allow for exchange of
gas and nutrients with tissue fluid
microcirculation
flow of blood into the bed via arterioles and blood exits via venules, blood flow through capillaries
continuous capillaries
formed by endothelial cells held together by tight junctions with interruptions called intercellular clefts which allow for the passage small solutes
fenestrated capillaries
cells of the endothelium contain many small pores, that allow for rapid passage of small solutes
sinusoids capillaries
wide winding capillaries with unusually large fenestration and wide intercellular clefts
venules
drain blood from most capillaries then join to form veins that return blood to heart
viens are lower in and higher in?
o2 and wastes
veins valves
prevent backward flow of blood when closed and make sure blood is moving towards the hearts
veins/venules carry about ____ of the bodys blood
64%
mechanisms of venous return
pressure gradient
gravity
cardiac suction
skeletal muscle pump
respiratory pump
circulatory shock
happens when CO is insufficient to meet body’s metabolic needs
arterial end
blood pressure > osmotic pressure
venous end
osmotic pressure > blood pressure
edema
accumulation of fluids in tissues that occur when fluid filtered out of blood and into tissues faster than it is reabsorbed back into blood.
right ventricular failure
lead to systemic edema
left ventricular failure
leads to pulmonary edema
reduced capillary reabsorption
reduced plasma albumin concentration - hyproteinemia can cause liver failure or edema
obstructed lymphatic drainage
the lymphatic system responsible for returning about 10% of tissue fluid back to blood, if blockage occurs with this reabsorb system, edema can result
flow
amount of blood flowing through an organ/tissue/blood vessels at any given time
perfusion
the flow per given volume or mass of tissue, usually in mL per 100 grams of tissue per minutes
blood pressure
force that blood exerts against vessel wall
where is BP measured
brachial artery
what device measures bp
sphygmomanometer
systolic pressure
peak arterial pressure during ventricular systole top #
diastolic pressure
minimum arterial pressure during ventricular diastole (relaxation) bottom #
hypotension
chronic low resting bp less then 90/60
hypertension
chronic resting bp higher then 140/90
pulse pressure
differences between diastolic and systolic pressures
factors affecting resistance
blood viscosity
vessel length
vessel radius/diameter
angiotensin II
strong vasoconstrictor that raises BP when too low
aldosterone
released from adrenal cortex, raises BP, signaling kidneys to retain sodium, urinate less.
ANP (atrial natriuretic peptide)
released from atrial cells, antagonist to aldosterone so lowers BP
ADH (antidiuretic hormone)
raises bp, by promoting water retension by kidney, released from posterior pituitary.
epinephrine and norepinephrine
released from adrenal medulla and sympathetic neurons casues vasoconstriction, raises BP.
simplest pathway
heart → arteries → capillaries → veins → heart
portal system
heart → arteries → 1st capillary bed → portal vein → 2nd capillary bed → veins → heart
arteriovenous anastomosis
heart → arteries → vein → heart
venous anastomoses
vein draining a capillary bed join w/ another vein to provide alt routes of blood draining from an organ. this is why vein blockages are not as life threatening as artery blocks
arterial anatomoses
when 2 arteries merge to provide collateral routes of blood supply to a tissue common in coronary circulation and around joints
the lymphatic system
network of vessels structures and organs that assists in circulating body fluids (lymph) and production of immune cells.
lymphatic system functions
fluid recovery
immunity
liquid absorption
lymph
clear colorless tissue that has left the tissue spaces and entered a lymphatic capillary
lymphatic pathways
lymphatic capillary → lymphatic vessels → lymph nodes →lymphatic vessels →lymphatic trunk → collecting ducts →subclavian veins
lymphatic trunks
jugular
subclavian
bronchomediastinal
intercostal
intestinal
lumbar
lymphatic collecting duct
thoracic
right lymphatic
trunks of draining into right lymphatic ducts
right jugular
right subclavian
right bronchomediastinal
trunks draining into thoracic duct
right/left lumbar
intestinal trunk
left bronchomediastinal
left subclavian
left jugular
flow of lymph is?
slow and low pressured
mechanism of the flow of lymph
lymphatic vessels contract
skeletal muscle contraction
respiratory movement
presence of valves
natural killer cells
large lymphocytes that target bacteria/infected host cells
t-lymphocytes
targets similar to NK cells
b-lymphocytes
antibody secreting cells that target a variety of pathogens
macrophages
phagocytic cells that target tissue debris, dead cells, bacteria, and other foreign materials
dendritic cells
mobile antigens presenting cells involved in activation of immune system
reticular cells
stationary APCs and found in lymphatic organs
MALT
diffuses lymphatic tissue located in connective tissue underlying mucous membrane
peyer’s patches
specialized clusters of MALT, underlying the epithial layer of the ileum in the small intestine
lymph flows into the lymph node via ?
afferent lymphatic vessels
lymph flows OUT of a lymph node via ?
efferent lymphatic vessels
lymph nodes filter out?
harmful particles out of lymph fluids
hilum
identation on concave side of node where efferents exit and arteries/veins enter and leave node
spleen function
filters blood
red pulp?
concentrated w rbcs; will remove old worn out rbcs and phagocytized by macrophages
white pulp?
regions concentrated with lymphocytes/macrophages monitor blood for foreign invaders
3 characteristics of innate immunity
local, non specific, and lacks memory
external barriers are???
skin, mucous membrane, and hair
phagocytosis
cellular eating by certain leukocytes
destruction of foreign particles by engulfing the foreign invader
macrophages
cells develop from larger wbcs such as monocyte; termed macrophages once they leave blood and take up phagocytic role
neutrophils
target bacteria in connective tissue consumed at the end of of their response to pathogen
interferon
protein released by some viral infected cells serves to protect neighboring cells
3 major processes of inflammation
mobilization of defenses
containment and destruction of pathogens
tissue cleanup and repair
adaptive immunity
systemic
specific
remember
cellular immunity
involves lymphocytes directly attacking and destroying foreign cells or diseased cells
humoral immunity aka (antibody mediated immunity)
involves production of antibodies which dont destroy pathogens, may be classified as passive or active.
antigens stimulate
the production of antibodies
APCS (antigen presenting cells)
b cells
macrophages
reticular cells
dendritic cells
mch stands for????
major histocompatibility complex
opsonization
coating antigens with antibodies to make antigens easier target of phagcytosis
precipitiation
enhances phagocytosis by grouping together individual cells or ag molecules making them immobile and less able to spread; easier targets for phagocytes
neturalization
blocks the ability of ag to adhere to host cells by coating the ag with abs, diminishes pathogenicity
complement fixation
abs interact.attract complement proteins causing cytolysis of microbial cell
cytotoxic t cells (Tc)
t cells that carry out direct attacks on antigens