normal HR and normal stroke volume
60-100 bpm about 100mL
structure of ventricles: r vs L structure of atria: R vs L
right ventricle has a thinner wall and lower pressure left atria is larger and lower pressure
NOT a syncytium like skeletal muscle central nuclei, sarcomeres, no end motor plates adjacent cells communicate via gap junctions
epicardium vs myocardium vs endocardium
epi - layer of CT and fat; additional layer of protection for the heart, under the pericardium. myo - muscle tissue, cardiomyocytes, endo - layer of endothelial cells and lines the inner surface of the heart; barrier and filtration
is nOT muscular
artery wall vs ventricle wall
artery wall is smooth muscle and ventricle is cardiac muscle
histology of purkinje fibers and location
larger and paler than myocytes
close to surface of endocardium
movement of blood?
oppose movement of blood?
three layers of vessel walls
intima, media, adventitia
pressure is pulsatile in the____
pressure decreases in vasculature going from ___ to ____
left ventricle to right atrium
what layer of vessel wall has CT and sparse smooth muscle?
what layer is thicker in arteries?
veins vs arteries
veins have irregular shape and thinner media(wall)
venules vs veins
venules have no smooth muscle while veins do
venules are smaller
what are the key controllers of resistance in vasculature?
arterioles and venules
is small vessels, ____ increases and ____ decreases
Surface area increases and velocity decreases
mechanism of smooth muscle activation
myosin light chain kinase phosphorylates myosin lt chain
what does myosin light chain (MLC) phosphatase do?
inhibits phosphorylation of MLC by MLC kinase
so inhibits contraction
cAMP and cGMP inhibit what?
thus inhibit contraction
Ca is required for ____ in skeletal muscle and ____ in endothelium
SM - contraction
endo - NOS induction
capillaries have NO what?
types of capillaries
Continuous capillaries are continuous, uninterrupted lining, only allow smaller molecules(water and ions) pass through; lipid-soluble molecules, can passively diffuse
Fenestrated capillaries have pores in the endothelial cells, allow small molecules and limited amounts of protein to diffuse. HAVE BASAL LAMINA
discontinuous capillary, larger openings, allow red and white blood cells and various serum proteins to pass aided by a discontinuous basal lamina. These capillaries lack pinocytotic vesicles, and therefore utilize gaps present in cell junctions to permit transfer between endothelial cells, and hence across the membrane. (marrow, lymph, and adrenal gland
contractile cells that wrap around the endothelial cells of capillaries and venules
respond to NO
lymphatic collecting vessels have
one way valves to prevent back flow
three tunic layers but thin and poorly defined