Exam 3- BIO 251: Test Questions and Answers 100%
Verified
Cardiac output is determined by what two variables?
A) stroke volume and ejection fraction
B) heart rate and ejection fraction
C) end-diastolic volume and end-systolic volume
D) heart rate and stroke volume
E) preload and afterload Correct Answer-D
Regulation of the heart (or any organ or tissue) by neural input, circulating hormones, or any
other factor originating from outside the organ is referred to as ________ control.
A) intrinsic
B) neurogenic
C) extrinsic
D) voluntary
E) myogenic Correct Answer-C
Which of the following structures is poorly innervated by the parasympathetic nervous
system and, therefore, an increase in parasympathetic activity has little effect on this
structure?
, Exam 3- BIO 251: Test Questions and Answers 100%
Verified
A) ventricles
B) conduction pathway
C) sinoatrial node
D) Purkinje fibers
E) atrioventricular node Correct Answer-A
The SA node is innervated by the
A) sympathetic nervous system only.
B) somatic nervous system only.
C) parasympathetic nervous system only.
D) sympathetic and parasympathetic nervous systems.
E) sympathetic, parasympathetic, and somatic nervous systems. Correct Answer-D
Which of the following is an effect of parasympathetic activity to the heart?
A) The rate of spontaneous depolarization in SA nodal cells decreases.
B) SA nodal cells are depolarized.
C) Heart rate is increased.
, Exam 3- BIO 251: Test Questions and Answers 100%
Verified
D) cAMP is activated.
E) Postganglionic neurons release acetylcholine, which binds to nicotinic cholinergic receptors
in
the SA node. Correct Answer-A
Which of the following is a FALSE statement about sympathetic activity to the SA node?
A) Norepinephrine binds to beta1 adrenergic receptors.
B) Potassium channel closing is enhanced.
C) cAMP levels in the pacemaker cells increases.
D) Funny channel opening is enhanced.
E) The rate of spontaneous depolarization is increased. Correct Answer-B
Under resting conditions, heart rate is primarily under the control of what control system?
A) the parasympathetic nervous system
B) the somatic nervous system
C) the sympathetic nervous system
D) intrinsic mechanisms
Verified
Cardiac output is determined by what two variables?
A) stroke volume and ejection fraction
B) heart rate and ejection fraction
C) end-diastolic volume and end-systolic volume
D) heart rate and stroke volume
E) preload and afterload Correct Answer-D
Regulation of the heart (or any organ or tissue) by neural input, circulating hormones, or any
other factor originating from outside the organ is referred to as ________ control.
A) intrinsic
B) neurogenic
C) extrinsic
D) voluntary
E) myogenic Correct Answer-C
Which of the following structures is poorly innervated by the parasympathetic nervous
system and, therefore, an increase in parasympathetic activity has little effect on this
structure?
, Exam 3- BIO 251: Test Questions and Answers 100%
Verified
A) ventricles
B) conduction pathway
C) sinoatrial node
D) Purkinje fibers
E) atrioventricular node Correct Answer-A
The SA node is innervated by the
A) sympathetic nervous system only.
B) somatic nervous system only.
C) parasympathetic nervous system only.
D) sympathetic and parasympathetic nervous systems.
E) sympathetic, parasympathetic, and somatic nervous systems. Correct Answer-D
Which of the following is an effect of parasympathetic activity to the heart?
A) The rate of spontaneous depolarization in SA nodal cells decreases.
B) SA nodal cells are depolarized.
C) Heart rate is increased.
, Exam 3- BIO 251: Test Questions and Answers 100%
Verified
D) cAMP is activated.
E) Postganglionic neurons release acetylcholine, which binds to nicotinic cholinergic receptors
in
the SA node. Correct Answer-A
Which of the following is a FALSE statement about sympathetic activity to the SA node?
A) Norepinephrine binds to beta1 adrenergic receptors.
B) Potassium channel closing is enhanced.
C) cAMP levels in the pacemaker cells increases.
D) Funny channel opening is enhanced.
E) The rate of spontaneous depolarization is increased. Correct Answer-B
Under resting conditions, heart rate is primarily under the control of what control system?
A) the parasympathetic nervous system
B) the somatic nervous system
C) the sympathetic nervous system
D) intrinsic mechanisms
