Physiology: Cardiac muscle Exam Questions
and Answers with Verified Solutions | Latest
Updated 2026
Located near the base of the right Sinoatrial node
atrium.
The SA node is the ______ Primary pacemaker
______ of
cardiac contraction under normal
conditions.
The SA node controls the rhythm heart rate
or
____ ____.
SA pacemaker activity is neural
modulated hormonal
by ______ (Vagus and
sympathetics)
and ______ influences.
Located at the junction of the right AV node
atrium.
T/F. The AV node can act as the True
pacemaker in pathological
conditions.
,Separates into two branches (one Bundle of His
to
each ventricle)
Purkinje fibers rapidly conduct the gap junctions
stimulus cell to cell via numerous
_____
_______ in order to rapidly spread
a
depolarization wave throughout
both of the ventricles.
T/F. Purkinje fibers are potential True
pacemakers.
Atrial myocytes tend to be _____ smaller
fibers
than ventricular myocytes/fibers.
Atrial myocytes contract _______ before
ventricular myocytes during the
cardiac cycle in order to move
blood
from atria to ventricles.
Ventricular myocyte fibers are Intercalated discs
interconnected in a branching Syncytium
array
and are joined at the _______
____. This
creates a ______.
, Invaginations of the sarcolemma T-tubules
(cell
wall) form __________.
What is the difference in T-tubule Cardiac: Located at the Z lines
location in cardiac muscle as Skeletal: Located at the A lines
opposed to skeletal muscle?
What do T-tubules allow for? Rapid transfer of substances across the
sarcolemma deep within the cell
_______ account for Mitochondria
approximately 23%
of the cell material.
The _______ _______ is well Sarcoplasmic reticulum
developed
and has a high calcium ion storage
capacity.
______ run longitudinally from end Myofibrils
of Sarcomeres
the fiber to the other and contain
well organized _______.
How many nuclei are present in One
cardiac muscle? What occurs in Multinucleated cells do exist
these? Protein synthesis occurs here
and Answers with Verified Solutions | Latest
Updated 2026
Located near the base of the right Sinoatrial node
atrium.
The SA node is the ______ Primary pacemaker
______ of
cardiac contraction under normal
conditions.
The SA node controls the rhythm heart rate
or
____ ____.
SA pacemaker activity is neural
modulated hormonal
by ______ (Vagus and
sympathetics)
and ______ influences.
Located at the junction of the right AV node
atrium.
T/F. The AV node can act as the True
pacemaker in pathological
conditions.
,Separates into two branches (one Bundle of His
to
each ventricle)
Purkinje fibers rapidly conduct the gap junctions
stimulus cell to cell via numerous
_____
_______ in order to rapidly spread
a
depolarization wave throughout
both of the ventricles.
T/F. Purkinje fibers are potential True
pacemakers.
Atrial myocytes tend to be _____ smaller
fibers
than ventricular myocytes/fibers.
Atrial myocytes contract _______ before
ventricular myocytes during the
cardiac cycle in order to move
blood
from atria to ventricles.
Ventricular myocyte fibers are Intercalated discs
interconnected in a branching Syncytium
array
and are joined at the _______
____. This
creates a ______.
, Invaginations of the sarcolemma T-tubules
(cell
wall) form __________.
What is the difference in T-tubule Cardiac: Located at the Z lines
location in cardiac muscle as Skeletal: Located at the A lines
opposed to skeletal muscle?
What do T-tubules allow for? Rapid transfer of substances across the
sarcolemma deep within the cell
_______ account for Mitochondria
approximately 23%
of the cell material.
The _______ _______ is well Sarcoplasmic reticulum
developed
and has a high calcium ion storage
capacity.
______ run longitudinally from end Myofibrils
of Sarcomeres
the fiber to the other and contain
well organized _______.
How many nuclei are present in One
cardiac muscle? What occurs in Multinucleated cells do exist
these? Protein synthesis occurs here
