Cardio Flashcards
2 kinds of loops
- Pulmonary loop
- Systemic loops
exchange vessels
capillaries
□ Q = P OVER R
Ohm’s law
Ohm’s law
P= PRESSURE GRADIENT Q= amount of flow R= resistance to flow
lets you determine the resistance to flow for a specific tube or blood vessel.
Poiseuille’s Law
R= 8Nl OVER pie r^4
Poiseuille’s Law
CHECK NOTES FOR BOTH EQUATIONS COMBINED
CHECK NOTES FOR BOTH EQUATIONS COMBINED
gets deoxygenated blood from
systemic loop;
Right Atrium
pumps blood out to
pulmonary loop.
Right Ventricle
gets oxygenated blood from pulmonary loop;
Left Atrium
pumps blood out to systemic loop
Left Ventricle
Great vein that empties into right atrium
Superior/Inferior Vena Cavae
Great vein that empties into left atrium
Pulmonary Vein
Great arteries that recieve blood from ventricles
Pulmonary Artery
Great arteries that receive blood
Aorta
prevent backflow from ventricle→atrium.
Atrioventricular Valves
2 types of atrioventricular Valves
Tricuspid & Mitral Valve
2 types of Semilunar valve
Pulmonic Valve and Aortic Valve
between pulmonary artery and right ventricle
Pulmonic Valve
between aorta and left ventricle.
Aortic Valve
Starting as deoxygenated blood arrives at the right atrium:
Right Atrium→Tricuspid Valve→Right Ventricle→Pulmonic Valve→Pulmonary Artery→Pulmonary Arteries→Pulmonary
Capillaries (Oxygenated)→Pulmonary Veins→Pulmonary Vein→Left Atrium→Mitral Valve→Left Ventricle→Aortic
Valve→Aorta→Systemic Arteries→Systemic Capillaries (Deoxygenated)→Systemic Veins→Superior or Inferior Vena
Cava→Right Atrium
the # of action potentials in cardiac cells
5 phases
Cardiac phases:
Phase 4: Membrane at Vrest. Phase 0: INa+ through VGNaCs→Depolarization Phase 1: Some IK+→Some repolarization Phase 2: ICa2+ →”Ca2+ plateau.” Phase 3: Large IK+ →Repolarization. Phase 4: Back to Vrest
Contraction in cardiac muscle is the result of
increase of Ca+2 in cytosol
Excitation-Contraction Coupling in cardiac is similar to skeletal muscle, but cause of ____ is different.
↑[Ca2+]cytosol
Explain Excitation-Contraction Coupling
- AP activates dihydropyridine receptors (aka: L-type Ca+2 channels)
- Intracellular Ca+2 activates ryanodine receptors in SR = Causing calcium release from SR into cytosol.
2 types cell types that make up heart
- contractile fibers
- Nodal fibers
Nodal fibers include:
sinoatrial node, atrioventricular node, Bundle of His.
Pacemaker potentials are present in _____
Nodal fibers
Pacemaker potentials include:
Phase 0: Ca2+ enters→rapid depolarization.
Phase 2: Small, brief Ca2+ plateau.
-Ca2+ continues to enter, but K+ begins to leave.
Phase 3: VGKCs activate. K+ leaves→rapid repolarization.
Phase 4: Slow, spontaneous depolarization brings membrane
to Vthresh—all on its own!
Nodal fibers can reach Vthresh and
fire APs all on their own, without any input.
Automaticity
allow for automaticity by allowing funny current to cross the membrane.
funny channels
Nodal fibers never sit at Vrest cz ?
—Funny channels activate upon repolarization and cause new depolarization
how often the heart beats and pumps blood—is the result of depolarization/APs originating in nodal fibers.
Heart rate
All cardiac cells—contractile and nodal fibers—are
Mononucleated cells
Every cardiac contractile and/or nodal cell is connected to its neighbors by
Gap junctions.
Gap junctions in the heart are known as:
Intercalated disk
___ is the “pacemaker”—where APs originate.
SAN- Sinoatrial Node
SAN Causes depolarization to spread out into atrial muscle down towards ventricles due to?
presence of funny channels that allow it to start depolarization on its own
how does depolarization spread through ventricular contractile fibers?
spreads from the bottom up