13.1 Physiology of Blood Circulation Flashcards
where is the cardiovascular center located
medulla oblongata
how is output sent from the cardiovascular center
via sympathetic and parasympathetic neurons
what are the functions of the sympathetic cardiac acclamatory nerves (2)
release the norepiniephrine increasing the rate of and force of the hearts contractions
cause vasoconstriction and an increase in blood pressure
what are the functions of the parasympathetic cardiac inhibitory nerves
release acetylcholine which decreases heart rate and has a lesser effect on decreasing the force of contraction
what is a function of the cardiovascular center
continuously sends impulses to the smooth muscle in blood vessel walls
What sets the rhythm of the hearts contractions?
specialized cardia cells called auto-rhythmic fibers, pacemaker cells
What does norepinephrine do to blood vessels
increase heart rate therefore constrict veins and arterioles
what does epinephrine do to blood vessels
dialate arterioles to increase blood flow
what is electrocardiography
the measurement and analysis of currents associated with heart activity
what is electrocardiography important for
the diagnosis of abnormal cardiac function
what is an ECG/EKG
the recording of the electrical changes of the heart
what does a normal electrocardiogram consist of
p wave
qrs complex
t wave
what does the p wave of an electrocardiogram indicate
atrial depolarization
what does the qrs complex of an electrocardiogram indicate
ventricular depolarization
what does the t wave of an electrocardiogram indicate
ventricular repolarization
what happened when acetylcholine was applied to a frog heart
it decreased the force of contraction
waves of the electrocardiogram got smaller and wider
what happened when epinephrine was applied to a frog heart
it increased the force of contraction
waves of the electrocardiogram gat taller and narrower
is epinephrine released by the sympathetic or parasympathetic system?
sympathetic
acetylcholine released by the sympathetic or parasympathetic system
parasympathetic
what does the term pulse refer to
alternating surges of pressure in an artery that can occur with each contraction and relaxation of the left ventricle
what is the normal resting pulse
70-76 beats per min
in clinical terms what does blood pressure refer to
arterial blood pressure
when heart muscle is in a contracted state what is it called
systole
when the heart muscle is in a relaxed state what is it called
diastole