15 The Heart Flashcards
what are the 4 chambers of the heart
two atria and two ventricles
Which chamber is located superiorly, receives blood and pump it to the ventricles
Atria
Which chamber is located posteriorly and pumps the blood away from the heart
Ventricles
What are the two groups of valves
Atrioventricular valves (tricuspid valve & bicuspid/mitral vlave)
Semilunar valves (aortic valve & pulmonary valve)
The right side of the heart receives ____ blood from the body
deoxygenated
What is the blood that the pulmonary artery carries
oxygen-poor blood
What is the blood that the pulmonary vein carries
oxygen-rich blood
-specialized cardiac muscle fibers of the heart
-can self-generate an action potential
-act as a pacemaker establishing the basic electrical activity in the heart
-form a conduction system
autorhythmic fibers
It is found in the wall of the right atrium, spontaneously depolarize thus becomes the pacemaker and establishes the sinus rhythm
Sinoatrial node
Depolarization of the SA node is followed by the generation of ____ and its spread throughout the atrium via the gap junction which connects neighboring cells.
action potential
This delays the action potential by about 0.1 seconds before it travels to the ventricles because of its smaller fibers and fewer gap junctions
AV node
From the AV node, the action potential moves to the AV bundle, also called the ____
bundle of His
What neurotransmitter slows down the SA node
acetylcholine (released by PNS)
What neurotransmitter accelerates the SA node
epinephrine (released by SNS)
type of nervous system that influences the rate of depolarization of the SA node
autonomic nervous system
