CV system Flashcards
What divides the heart so the right side is separate from the left side?
the septum
What does the heart do as a pump?
it creates pressure gradient and fluids and the heart has a pump on right and on the left
What does the right atrium receive?
venous blood from the whole body via the superior inferior vena cava and the coronary vein
-blood away from the heart the vessel is an artery and if a vessel carries blood to the heart it is a vein
-arteries branch into smaller and smaller arteries which branch into arterioles which feed into capillaries which can inly exchange material cause they are so thin and leaky - capillaries drain into venues which are small veins and tiny veins and then bigger veins - left ventricle pumps into main systemic artery which is the aorta and the right ventricle pumps into the pulmonary artery going to the lungs
-the pulmonary vein comes from the lungs to the left atrium and the main systemic veins are the superior and inferior vena cava which drain the systemic part of the artery everything in the body which is not the lungs
-there are valves strategically located to prevent back flow and there’s four of them between atrium and ventricles and ventricles and artery
What is the cardiac output and how much blood does the left side receive compared to the right side?
the amount of blood pumped per min so 5L/min is strandrad - systemic system and pulmonary system CO is the same
What are the three places there are portal vessels?
digestives tract to liver via hepatic portal veins
kidney to kidney via renal portal vein
hypothalamus to ant pit via hypothalamic hypophyseal portal veins
What are the four valves of the heart?
atrioventricular valves - right atria and right ventrcile - tricsupid valve - left atria and left ventricle is the bicsupid valve and that is the mitral valve
semilunar valves - aortic and pulmonary valve
How are cardiac muscle cells similar to skeletal muscle?
striated and t tubules and SR
How are cardiac muscle cells similar to smooth muscle?
are spontaneous and involuntary
-have Ecf calcium channel
What two things do intercalated discs have?
desmosomes - align contraction
gap junction - align electrical activity
What is Pouisuelle’s Law?
R = 8Ln/pi r^4
n is viscosity
What causes the AP of cardiac cells to be longer and what does a longer AP allow for?
calcium channels
-longer AP is longer refractory period so heart can fill
When Phospholamban is not phosphorylated what does it do compared to when it is?
inhibits the SR Ca ATPase when not P
when P does not inhibit the pump increasing calcium stores
2 atria and 2 ventricles and the pink stuff is the contractile muscle cells which wrap around the heart and the purple tissue is the pacemaker of the heart and conducting elements of the heart and this is the SA node and is. Between the superior vena cava and the right atrium embedded in the walls of the right atrium - this SA side has cells which generate the pacemaker AP like on the previous slide right hand slide - these cells are connected by gap junctions and are all in sync and because the AP spreads trough all the gap junctions
-the contractual muscle cells are connected to the right atrium SA node by gap junction and so that when the SA node fires an AP that AP spreads through the gap junctions and contractual cells and align the electrical activity
-these ap in the contractual tissues spread from cell to cell to cell - the SA node causes AP to spread to specialized muscle cells which do not contract but conduct APs and the APs spread from muscle cell to muscle cell from the right atrium to the left atrium because there is gap junctions between the right atrial cells and the left atrial cells spreads right across - the AP while doing this is spreading from AP conducting muscle cells which do not contract and just cionvey the AP quicklo a pice of nodal tissue whintimateetween the right atrium and right ventricle atrioventricular node and once the AP gets in the AV node the AP slows down compared to the conducting cells it was in - eventually the AP gets to the far side of the node and spreads to other modified muscles fibers that are elongated like nerve axons but they do not conauteurwhich are called purkinje fibers and they comgenerate AV node and split into two bundles teh right bundlthatthate left bundle and they go down the septum or the partition between two ventricles and convey the AP to the bottom of the heart which is called the apex and there the purkinje fibers split out of the bundle and make gap junctions on the contractual cells and intitate the contractual muscle cells and the contraction of the heart muscle at the bottom of the apex and from there the AP spreads up which is good because that AP is causing the contraction and the contraction is squeexing the blood the arteries through which blood leaves the ventrciels are at the top and the pulmonary arteur and the aorta - all parts of the heart can genearte and AP spontaneously and we saw a little clump of cells taht could do it - the pacemaker tissue the sa node and the av node workls in such a way that generates an AP at the highest frequnecy and with the most regular rhythym - the sa node generates ap at a higher frequency than the av node does so the sa node is the pacemaker for the whole cell because ti generate the AP that spreads through the whilke heart and this also spreads to the av node which triggers contractions - the heart needs to beat in a certain sequnece because it hasj to fill the vsicous blood and eject it
-sa node is pacemaker of the heart
-when the rate in rise of an AP is slow that slows down the conduction velocity of an AP
