1
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Medical Physiology PHSL 1010: Exam 2
Questions and Answers (100% Correct
Answers) Already Graded A+
Depolarizing currents pass to the sarcoplasmic reticulum via:—
Ans: T-tubules (triads)
The muscle protein that binds to Ca++ during excitation-
contraction coupling is:— Ans: Troponin
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A skeletal muscle fiber comprises:— Ans: One muscle cell only
Fast-twitch muscle fibers differ from slow-twitch fibers in which
way(s)?— Ans: Slow-twitch fibers have more myoglobin than fast-
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twitch AND Slow-twitch fibers are more fatigue-resistant than fast-
twitch
Smooth muscle differs from skeletal muscle in which way(s)?—
Ans: Smooth muscle cells have only one nucleus AND Smooth
muscle contracts more slowly than skeletal muscle
Smooth muscle dense bodies perform a similar function to:— Ans:
Z lines (from striated [cardiac & skeletal] muscles)
Parasympathetic ganglia that aid in control of smooth muscle
contraction are located:— Ans: Inside sheets of smooth muscle
The correct sequence of events in smooth muscle contraction is:—
Ans: Ca++ enters the cell, Ca++ binds to calmodulin, myosin
heads are phosphorylated, myosin binds to actin
Cardiac muscle differs from skeletal muscle in which way(s)?—
Ans: Cardiac muscle cells have only one nucleus and are
branched
Intercalated disks:— Ans: Both serve as the insertion point for
cardiac muscle cells and contain numerous gap junctions and
desmosomes
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Excitation-contraction coupling in cardiac muscle:— Ans: Is both
limited by parasympathetic activity and is similar to that seen in
skeletal muscle
Action potentials in cardiac muscle cells:— Ans: Are
characterized by a broad plateau as Ca++ enters the cell
Depolarizing signals pass through the atrial musculature via:—
Ans: Gap junctions
The first "heart sound" is made by:— Ans: Closure of the mitral
valve AND Closure of the tricuspid valve
The greatest blood pressure is achieved at:— Ans: Atrial diastole
Papillary muscles:— Ans: Anchor the leaflets of the A-V valves
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AND Are inserted into the ventricular musculature
Cardiac output:— Ans: Varies with heart rate (and stroke
volume)
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The Frank-Starling Law of the Heart shows that cardiac muscle:—
Ans: Achieves maximum force when muscle fibers are stretched
AND Achieves maximum force when end diastolic volume is
greatest
Contractility of the heart:— Ans: Can be enhanced by
catecholamines
Arteries differ from veins in which way?— Ans: Arteries have more
elastic fibers in the tunica media than veins
Mean arterial pressure is directly proportional to:— Ans: Cardiac
output and arterial resistance
Arterial resistance:— Ans: Is affected by stress, emotion,
epinephrine, and by sympathetic stimulation
The renin-angiotensin system:— Ans: Affects blood pressure by
altering blood volume AND Is initiated by sensors in the macula
densa of the kidney.
does NOT stimulate aldosterone release, which promotes water
loss
For Expert help and assignment solutions, +254707240657
Medical Physiology PHSL 1010: Exam 2
Questions and Answers (100% Correct
Answers) Already Graded A+
Depolarizing currents pass to the sarcoplasmic reticulum via:—
Ans: T-tubules (triads)
The muscle protein that binds to Ca++ during excitation-
contraction coupling is:— Ans: Troponin
© 2025 Assignment Expert
A skeletal muscle fiber comprises:— Ans: One muscle cell only
Fast-twitch muscle fibers differ from slow-twitch fibers in which
way(s)?— Ans: Slow-twitch fibers have more myoglobin than fast-
Guru01 - Stuvia
twitch AND Slow-twitch fibers are more fatigue-resistant than fast-
twitch
Smooth muscle differs from skeletal muscle in which way(s)?—
Ans: Smooth muscle cells have only one nucleus AND Smooth
muscle contracts more slowly than skeletal muscle
Smooth muscle dense bodies perform a similar function to:— Ans:
Z lines (from striated [cardiac & skeletal] muscles)
Parasympathetic ganglia that aid in control of smooth muscle
contraction are located:— Ans: Inside sheets of smooth muscle
The correct sequence of events in smooth muscle contraction is:—
Ans: Ca++ enters the cell, Ca++ binds to calmodulin, myosin
heads are phosphorylated, myosin binds to actin
Cardiac muscle differs from skeletal muscle in which way(s)?—
Ans: Cardiac muscle cells have only one nucleus and are
branched
Intercalated disks:— Ans: Both serve as the insertion point for
cardiac muscle cells and contain numerous gap junctions and
desmosomes
, 2
For Expert help and assignment solutions, +254707240657
Excitation-contraction coupling in cardiac muscle:— Ans: Is both
limited by parasympathetic activity and is similar to that seen in
skeletal muscle
Action potentials in cardiac muscle cells:— Ans: Are
characterized by a broad plateau as Ca++ enters the cell
Depolarizing signals pass through the atrial musculature via:—
Ans: Gap junctions
The first "heart sound" is made by:— Ans: Closure of the mitral
valve AND Closure of the tricuspid valve
The greatest blood pressure is achieved at:— Ans: Atrial diastole
Papillary muscles:— Ans: Anchor the leaflets of the A-V valves
© 2025 Assignment Expert
AND Are inserted into the ventricular musculature
Cardiac output:— Ans: Varies with heart rate (and stroke
volume)
Guru01 - Stuvia
The Frank-Starling Law of the Heart shows that cardiac muscle:—
Ans: Achieves maximum force when muscle fibers are stretched
AND Achieves maximum force when end diastolic volume is
greatest
Contractility of the heart:— Ans: Can be enhanced by
catecholamines
Arteries differ from veins in which way?— Ans: Arteries have more
elastic fibers in the tunica media than veins
Mean arterial pressure is directly proportional to:— Ans: Cardiac
output and arterial resistance
Arterial resistance:— Ans: Is affected by stress, emotion,
epinephrine, and by sympathetic stimulation
The renin-angiotensin system:— Ans: Affects blood pressure by
altering blood volume AND Is initiated by sensors in the macula
densa of the kidney.
does NOT stimulate aldosterone release, which promotes water
loss
