FINAL EXAM: Unit 4 Flashcards
describe the pathway of blood in the heart (start at right atrium)
- right atrium (low O2)
- tricuspid valve
- right ventricle
- pulmonary semilunar valve
- pulmonary trunk
- pulmonary arteries (low O2)
- lungs
- pulmonary veins (high O2)
- left atrium
- bicuspid valve
- left ventricle
- aortic valve
- aorta (high O2)
- systemic tissues
- inferior & superior vena cave (low O2)
what two factors lead to flow?
pressure (+)
resistance (-)
what three factors lead to resistance?
length (+)
viscosity (+)
radius (-)
what two factors lead to velocity?
flow rate (+)
area (-)
what two factors lead to MAP (mean arterial pressure)?
CO (+)
resistance (+)
what two factors lead to cardiac output?
HR (+)
stroke volume (+)
what is stroke volume?
volume of blood pumped by one ventricle during a contraction
what happens to SV when force of contraction increases?
SV increases
what does phospholambin do to SV?
increases SV
-positive ionotropic agent (increases force of contraction)
what is the equation for SV?
SV = EDV - ESV
what three factors lead to EDV / venous return?
skeletal pump (+)
respiratory pump (+)
sympathetic NS - alpha (+)
what is the equation for ejection fraction?
EF = SV / EDV * 100
what does the parasympathetic NS do to HR?
decreases HR
-ACh (musc -> hyper)
what does the sympathetic NS do to HR?
increases HR
-NE (beta1 -> depo)
what is preload and afterload?
preload: stretch heart must overcome to fill with flood
afterload: force needed to push blood to the arteries
what happens to force when you increase sarcomere length?
increases force
what happens during the depolarization phase in a cardiac contractile cell AP?
Na+ entry
what happens during the peak of the cardiac contractile cell AP?
K+ exits
Ca2+ entry
what happens during the repolarization phase of cardiac contractile cell AP?
Ca2+ channels close
K+ exits
what happens during the depolarization phase in a cardiac autorhythmic cell AP?
I(f) channels open
Na+ entry
Ca2+ entry
what happens during the repolarization phase in a cardiac autorhythmic cell AP?
K+ exits
what is the electrical conduction pathway in the heart
- SA node
- AV node
- AV bundle (AV delay)
- bundle branches
- purkinje fibers (bottom to top)
what is happening during the P wave in an ECG?
atrial depolarization
SA node fires
what is happening during the QRS wave in an ECG?
ventricle depolarization
what is happening during the T wave in an ECG?
ventricle repolarization
what is happening during the PR segment? ST segment?
PR: atria contract, AV delay
ST: ventricle contract
what are the five phases in the cardiac cycle?
- active filling
- isovolumic ventricle contraction
- ventricular ejection
- isovolumic ventricle relaxation
- passive filling
what is happening during active filling? (what contracts, aorta valve, semilunar valve, volume, pressure)
atria contract
ventricle relax
AV open
SL closed
ventricle volume increases
pressure same
EDV MEASUREMENT
what is happening during isovolumic ventricle contraction? (what contracts, aorta valve, semilunar valve, volume, pressure)
atria relax
ventricle contract
AV & SL closed (lub)
volume same
pressure increases
what is happening during ventricle ejection? (what contracts, aorta valve, semilunar valve, volume, pressure)
atria relax
ventricle contract
AV close
SL open
volume decreases
pressure decreases
what is happening during isovolumic ventricle relaxation? (what contracts, aorta valve, semilunar valve, volume, pressure)
atria & ventricle relax
AV & SL closed (dub)
volume same
pressure decreases
what is happening during passive filling? (what contracts, aorta valve, semilunar valve, volume, pressure)
atria & ventricle relax
AV open
SL closed
volume increases
pressure same
what is an artery?
all types
-thickest
-blood AWAY from heart
-pressure reservior
what is an arteriole?
endothelium & smooth muscle
-main site of regulation
-contain a precapillary sphincter
what is a capillary?
endothelium
-leaky (pericytes increase leakiness)
-smallest -> lowest velocity
what is a venule?
endothelium & fibrous tissue
what is a vein?
all types
-valves for 1-way flow
-majority
-low pressure
-blood TO the heart
-volume reservoir
what is blood pressure?
the strength of blood moving through vessels
120/80 (systolic/diastolic)
what is the equation for pulse pressure?
systole - diastole
what happens to BP when MAP increases?
BP increases
what is the equation for MAP?
diastole + 1/3 (pulse pressure)
what happens to BP when blood volume increases?
BP increases
how do you fix a high BP?
vasodilation to decrease MAP
what are vasoconstrictors for BP?
NE (alpha)
vasopressin/ADH
angiotension 2
leads to a decrease in BP
what are vasodilators for BP?
E (beta2)
NO
low O2 = high CO2
histamine
natriuretic peptides (ANP)
leads to an increase in BP
what is the difference b/w active and reactive hyperemia?
active: increase flow due to increased metabolism
reactive: increase flow due to occulsion
what is the pathway for the baroreceptor reflex? (low BP)
- low BP
- decrease firing rate of baroreceptor
- sensory neurons
- CVCC in medulla oblongata
- increase symp (alpha) activity, decrease parasym activity
- constriction
- increase BP
what is the difference between continuous, fenestrated, and sinusoid capillaries?
continuous: majority, only pass solutes & gases & glucose
fenestrated: can pass more fluid
sinusoid: can pass proteins and cells
what is the difference b/w diffusion and transcytosis?
diffusion: small solutes move w/ conc. gradient
transcytosis: large solutes move by vesicular transport
what two forces make up bulk flow? describe them
hydrostatic pressure: pressure on walls, FILTRATION, push fluids out of blood, high on arterial end, (+)
colloid osmotic pressure: plasma proteins, ABSORPTION, keep fluids in blood, high on venous end, constant # (-)
what is edema? how does the lymphatic system impact edema?
swelling, net filtration
-lymph system returns fluid that is lost at capillaries
describe the role of the plasma proteins (albumins, globulins, fibrinogen, transferrin)
albumins: majority, lead to colloid osmotic pressure
globulins: antibodies, protein carries, clotting factors
fibrinogen: fibrin threads, clot formation
transferrin: transports iron
what is anemia?
decreased O2 carrying capacity
-fewer RBCs
what leads to hematopoiesis of white blood cells?
interleukins & colony-stimulating factors
describe the role of the white blood cell types (lymphocyte, monocyte, neutrophil, basophil, eosinophil)
lymphocyte: T & B cells, immune response
monocyte: turn into macrophages, phagocytic
neutrophil: majority, mobile, first to arrive at site
basophil: histamine granules, allergy response
eosinophil: parasitic infections, allergy response
what are the precursors for RBCs?
erthyroblast: nucleus
reticulocyte: no nucleus
what is hemoglobin?
carries O2
-4 peptide chains (alpha, beta)
-contains heme group (iron)
describe the hemotopoiesis of RBCs (erthropoietin)
- low O2
- EPO release by kidney
- goes to bone marrow
- increases RBC production
- increases hemoglobin
- increases O2
what is the precursor for platelets?
megakaryocytes
-NO NUCLEUS
what is the process of hemostasis?
- vasoconstriction
- platelet plug
- coagulation
what is the platelet plug pathway?
- exposed collagen
- activates platelets
- release factors that have positive feedback on the pathway
what are the functions of the factors released in the platelet plug pathway? (platelet activating factor, van willibrand factor, thromboxane A2)
platelet activating factor: activate platelets
van willibrand factor: adhere platelets
thromboxane A2: activate platelets
what two things stop the platelet plug pathway?
stop adherence
-prostacylin, NO
describe the coagulation cascade
- INTRINSIC: exposed collagen -> factor 12
- EXTRINSIC: damage -> factor 3 -> factor 7
- factor 10
- prothrombin -> thrombin
- fibrinogen -> fibrin
- factor 13
what is fibrinolysis?
removal of the clot
-plasminogen -> plasmin (TPA)
what is thrombopoietin?
hematopoiesis of platelets
-in the liver
what is the process of a pluripotent hematopoietic stem cell?
uncommitted cell -> progenitor cell
what is the difference b/w red and yellow marrow?
red: hematopoiesis, red color from hemoglobin
yellow: no hematopoiesis, high fat levels
