A&P II Exam 1
The anticholinergic drug atropine blocks muscarinic receptors. This drug is often administered to treat bradycardia or slow heart rate. What affects does it have on the patient when it is administered? View Available Hint(s) Atropine will block the actions of the vagus nerve on the heart resulting in a decreased heart rate. Atropine will enhance the actions of the vagus nerve on the heart resulting in an increased heart rate. Atropine will block the receptors on the parasympathetic target cells resulting in a decreased heart rate. Atropine will block the actions of the vagus nerve on the heart resulting in an increased heart rate.
Atropine will block the actions of the vagus nerve on the heart resulting in an increased heart rate.
The plateau phase of the cardiac action potential is due to __________. Na+ influx Cl- influx K2+ influx Ca2+ influx
Ca2+ influx
Sometimes health care providers will elect not to treat conditions such as atrial fibrillation in which there is no functional atrial contraction. Select the logic behind this. View Available Hint(s) Treating the atrial fibrillation will lead to increase in bradycardia, thereby increasing the force of contraction exceeding the normal strength. If there is no functional atrial contraction, the heart will fail regardless. Most of the blood drains from the atria passively into the ventricles. Treating the condition would leave the atrioventricular valves open and lead to backflow.
Most of the blood drains from the atria passively into the ventricles.
Which wave on the electrocardiogram (ECG) corresponds with the ventricular filling phase of the cardiac cycle? S wave T wave P wave S-T segment
P wave
A damaged atrioventricular (AV) bundle or atrioventricular (AV) node will primarily affect the length of the: T wave. Q-T interval. P wave. P-R interval.
P-R interval
Describe the pressures in the atria and ventricles that would cause the opening of the AV valves. View Available Hint(s) Pressures in the atria and ventricles would be equal. Pressure in the ventricles would be greater than in the atria. Pressure in the atria would be greater than the pressure in the ventricles.
Pressure in the atria would be greater than the pressure in the ventricles.
Which part of the electrocardiogram (ECG) would most be affected by abnormally slow depolarization of the ventricles? R-T interval P wave QRS wave T wave
QRS wave
An elderly woman taking medication to lower her blood pressure will see effects on her entire sympathetic nervous system. What would happen if she is faced with an emergency? View Available Hint(s) She will be more able to regulate her blood pressure and make the necessary adjustments during the emergency. She will be less able to regulate her blood pressure and more able to make other adjustments during the emergency. She will be less able to regulate her blood pressure and make the necessary adjustments during the emergency. She will be more able to regulate her blood pressure but less able to make other adjustments during the emergency.
She will be less able to regulate her blood pressure and make the necessary adjustments during the emergency.
What normally serves as the pacemaker of the entire heart? atrioventricular (AV) node atrioventricular (AV) bundle sinoatrial (SA) node Purkinje fiber system
SA node
Which part of the intrinsic conduction system normally initiates the depolarizing impulse that causes a heartbeat? View Available Hint(s) Internodal pathway AV bundle AV node SA node
SA node
Predict the position of the valves during the ventricular ejection phase. The AV valves and semilunar valves are shut. The AV valves are shut while both semilunar valves are forced open. The AV valves are forced open while both semilunar valves are shut. The AV valves and semilunar valves are forced open.
The AV valves are shut while both semilunar valves are forced open.
Determine the impact if the connection between the sinoatrial (SA) node and the atrioventricular (AV) node becomes blocked. The ventricles will contract more quickly. The ventricles will contract more slowly. The atria will contract more forcefully. The ventricular rhythm will not change.
The ventricles will contract more slowly.
The long length of the cardiac action potential, at 200-300 msec, allows for: less calcium ions to enter cells. a faster heart rate. a reduction in strength of the heart's contraction. an opportunity for the heart to fill with blood.
an opportunity for the heart to fill with blood.
Unlike autonomic motor neurons, somatic motor neurons __________. synapse with their target cells inside ganglia release ACh at their target cells can only stimulate their target cells and not inhibit them stimulate cardiac muscle, smooth muscle and glands
can only stimulate their target cells and not inhibit them
Compared to parasympathetic ganglia, sympathetic ganglia are __________. located in brain stem closer to the spinal cord located in the thoracic or lumbar spinal cord embedded in the target organs
closer to the spinal cord
Which of the following can be heard with a stethoscope most easily? View Available Hint(s) Contraction of atria Blood flow into aorta Isovolumetric contraction Closing of atrioventricular valves
closing of atrioventricular valves
The beginning of the QRS complex of the electrocardiogram (ECG) immediately precedes which of the following events? View Available Hint(s) closing of the atrioventricular valves closing of the semilunar valves blood ejection from the ventricles atrial contraction
closing of the atrioventricular valves
The rapid influx of calcium ions into pacemaker cells creates a positive membrane potential inside the cell and is responsible for the: minimum potential phase. full depolarization phase. repolarization phase. slow initial repolarization phase.
full depolarization phase
What causes the aortic semilunar valve to close? View Available Hint(s) equal ventricular and aortic pressures higher ventricular pressure than aortic pressure greater pressure in the aorta than in the left ventricle
greater pressure in the aorta than in the left ventricle
Ephedrine is a protein extracted from a Chinese plant that acts similarly to epinephrine and acts on the same receptors. Ephedrine can cause __________. increased heart rate bronchoconstriction constriction of the pupil increased digestive functions
increased heart rate
What ion movement changes the membrane potential in a contractile cell from negative to positive during the rapid depolarization phase? outflow of potassium ions influx of calcium ions influx of sodium ions outflow of calcium ions
influx of sodium ions
What surface groove separates the right and left ventricles? interatrial septum atrioventricular sulcus interventricular septum interventricular sulcus
interventricular sulcus
Ventricular systole begins during the __________ phase of the cardiac cycle. ventricular filling isovolumetric relaxation ventricular ejection isovolumetric contraction
isovolumetric contraction
Put the phases of the cardiac cycle in the correct order, starting after ventricular filling. View Available Hint(s) isovolumetric contraction, ventricular ejection, isovolumetric relaxation ventricular ejection, isovolumetric contraction, isovolumetric relaxation isovolumetric relaxation, ventricular ejection, isovolumetric contraction ventricular ejection, ventricular relaxation, isovolumetric contraction
isovolumetric contraction, ventricular ejection, isovolumetric relaxation
When is the S2 heart sound heard? isovolumetric relaxation phase isovolumetric contraction phase ventricular filling ventricular ejection phase
isovolumetric relaxation phase
Which heart chamber receives blood from the pulmonary veins? View Available Hint(s) left atrium right ventricle left ventricle right atrium
left atrium
Which chamber pumps oxygenated blood out the aorta to the systemic circuit? View Available Hint(s) right atrium left atrium left ventricle right ventricle
left ventricle
Which of the following valves would be affected if papillary muscles and/or chordae tendinae stopped functioning? Aortic valve None of the answers are correct Pulmonary valve Mitral valve
mitral valve
Which of the following is correct about the filling of the ventricles? View Available Hint(s) Most blood flows passively into the ventricles through open AV valves. The majority of ventricular filling is caused by contraction of the atria.
most blood flows passively into the ventricles through open AV valves
After eating a large meal, Mr. Davis felt sleepy. Which nervous system dominates and is often called our "rest and digest" division of the autonomic nervous system (ANS)? parasympathetic nervous system sympathetic nervous system somatic nervous system systemic nervous system
parasympathetic nervous system
What do pacemaker cell action potentials lack? plateau phase threshold repolarization depolarization
plateau phase
Which of the following innervates target cells or organs of the autonomic nervous system (ANS)? somatic motor neuron postganglionic neuron preganglionic neuron autonomic ganglion
postganglionic neuron
The AV valves close when __________. pressure in the ventricles increases pressure in the ventricles decreases pressure in the aorta increases pressure in the atria increases
pressure in the ventricles increases
What is the function of the valves in the heart? invert during contraction of the ventricles prevent backflow of blood through the heart promote contraction of the ventricles eliminate pressure variances within the heart
prevent backflow of blood through the heart
A damaged right bundle branch will prevent the passage of the action potential to the: Purkinje fibers in the right ventricle. sinoatrial (SA) node. atrioventricular (AV) node. atrioventricular (AV) bundle.
purkinje fibers in the right ventricle
Which chamber receives blood from the superior and inferior vena cavae? View Available Hint(s) right ventricle right atrium left ventricle left atrium
right atrium
Which heart chamber pumps unoxygenated blood out the pulmonary trunk? View Available Hint(s) right atrium left ventricle left atrium right ventricle
right ventricle
Autonomic motor neurons do NOT innervate: glands. smooth muscle cells. cardiac muscle cells. skeletal muscle cells.
skeletal muscle cells
Which division of the nervous system is responsible for voluntary control of skeletal muscle? somatic nervous system visceral motor division parasympathetic nervous system sympathetic nervous system
somatic nervous system
Which of the following is called the "fight or flight" division of the nervous system? somatic motor division visceral sensory division parasympathetic nervous system sympathetic nervous system
sympathetic nervous system
Beta-blockers are a class of drugs that act as adrenergic antagonists. Beta-blockers will have an effect at __________. parasympathetic ganglia parasympathetic target organs sympathetic target organs sympathetic ganglia
sympathetic target organs
The vessels that deliver oxygen to the tissues of the body are part of the __________. conducting circuit coronary circuit systemic circuit pulmonary circuit
systemic circuit
Archie has a resting heart rate of 125 beats per minute. Classify his cardiac dysrhythmia. bradycardia heart block asystole tachycardia
tachycardia
As a result of the long refractory period in the contractile cell, cardiac muscle can NOT exhibit: treppe. oxygen debt. tetany. fatigue.
tetany
Where do the cell bodies of preganglionic neurons of the sympathetic nervous system originate? thoracic and upper lumbar regions of the spinal cord cranial nerves and the lumbar region of the spinal cord cervical region and sacral region of the spinal cord cranial nerves and the sacral region of the spinal cord
thoracic and upper lumbar regions of the spinal cord
Pressure in the aorta is greater than pressure in the pulmonary trunk; therefore, the left ventricle has to generate a greater pressure than the right ventricle in order to eject blood from the heart. True False
true
The heart is actually (one, two, or three) pumps? View Available Hint(s) three pumps two pumps one pump
two pumps
Both the left and right atria receive blood from: the ventricles. arteries. the lungs. veins.
veins
Isovolumetric relaxation and ventricular filling (two phases of the cardiac cycle) take place during __________. View Available Hint(s) ventricular systole ventricular diastole
ventricular diastole
The T wave of an ECG corresponds to __________. ventricular repolarization atrial repolarization atrial depolarization ventricular depolarization
ventricular repolarization
Visceral reflex arcs do NOT control: voluntary muscle functions. blood pressure. digestion. heart rate.
voluntary muscle functions
Place the following parts of the cardiac conduction system in the order in which they transmit the action potential. 1. atrioventricular (AV) bundle 2. Purkinje fibers 3. sinoatrial (SA) node 4. right and left bundle branches 5. contractile cells of cardiac muscle tissue 6. atrioventricular (AV) node 3, 6, 1, 4, 2, 5 3, 1, 6, 4, 5, 2 3, 6, 4, 1, 2, 5 3, 1, 6, 4, 2, 5
3, 6, 1, 4, 2, 5
The amount of blood remaining in each ventricle at the end of the ventricular ejection phase is normally about: 50 ml. 120 ml. 30 ml. 70 ml.
50 mL
Which of these structures conduct(s) action potentials the slowest? View Available Hint(s) Purkinje fibers Bundle branches AV bundle AV node
AV node
Increased pressure in the ventricles would close what valve(s)? View Available Hint(s) semilunar valves only both semilunar and AV valves AV valves only
AV valves only
