Exam 2--> Hearts
End diastolic volume is the: A. volume of blood in the ventricle at the end of ventricular relaxation B. volume of blood in the atrium at the end of atrial relaxation C. the amount of blood ejected into the aorta D. the total volume of blood in the entire heart at the end of one heartbeat
A
In a healthy young adult, what happens to cardiac output when heart rate increases above 160 bpm? It increases. There is no way to predict. It decreases. It remains constant.
A
Stroke volume is defined as: A. the amount of blood ejected from the ventricle during one contraction. B. the number of times the heart contracts in one minute. C. the product of the heart rate and rhythm. D. the amount of blood received into the atrium with each heartbeat.
A
If the heart rate for a patient is 80 bpm, and her stroke volume is 70 mL/beat, then her cardiac output is: A. 0.87 mL/min B. 5600 mL/min C. 56 mL/min D. 1.1 mL/min
B
Into which chamber of the heart do the pulmonary veins deliver blood? A. Right atrium B. Left atrium C. Right ventricle D. Left ventricle
B
What part of the heart may be considered the systemic circuit pump? A. The left atrium B. The left ventricle C. The right atrium D. The right ventricle
B
Which is the correct sequence of layers in the heart wall, starting with the outermost layer? A. Myocardium, pericardium, endocardium B. Epicardium, myocardium, endocardium C. Endocardium, epicardium, myocardium D. Endocardium, smooth muscle, epicardium
B
A patient is brought to the Emergency Department complaining of shortness of breath, light-headedness, and nausea. During the initial examination, an EKG indicated that the patient had nodal rhythm. Based on what you currently know from this class, what is possible explanation for this finding? A .The patient has a bundle branch block causing multiple PVCs. B. The patient has had too much caffeine causing the AV node to malfunction. C. The patient has experienced a heart block causing the SA node to malfunction. D. The patient has had a heart attack causing death of the heart muscle.
C
After the end of __________, the ventricles are 70% filled. active ventricular filling atrial systole passive ventricular filling ventricular systole
C
The inner lining of the visceral pericardium is adherent to the: A. myocardium B. epicardium C. endocardium D. pericardial cavity
C
correct sequence of blood flow through the chambers of the heart
Right atrium → right ventricle → pulmonary artery → left atrium → left ventricle → aorta
Correct sequence of current flow through the heart wall
SA node → AV node → AV bundle → right and left bundle branches → Purkinje fibers
Cardiac Output (CO)
product of heart rate and stroke volume
The cardiac cycle consists of a distinct relaxation and contraction phase. Which term is typically used to refer ventricular contraction while no blood is being ejected? A. Isovolumetric contraction B. Diastole C. Quiescent D. Systole
A
The force the heart must overcome to pump blood into the pulmonary artery and aorta is known as ________. afterload stroke volume cardiac output preload
A
The most muscular chamber of the heart is the: A. left ventricle B. left atrium C. right ventricle D. right atrium
A
The normal pacemaker of the heart is the: SA node Bundle branches Purkinje fibers AV bundle AV node
A
What nerve carries parasympathetic fibers to the sinoatrial (SA) node? Vagus Facial Accessory Hypoglossal
A
Which of these conditions is most likely to cause bradycardia? Damage to the tricuspid valve Too much coffee Excessive parasympathetic stimulation Excessive sympathetic stimulation
A
Which of these statements concerning cardiac muscle is correct? A. Cardiac muscle has a prolonged period of slow repolarization called the plateau phase. B. Depolarization of cardiac muscle occurs when K+ and Na+ diffuse into the cell. C. Cardiac muscle has more sarcoplasmic reticulum than skeletal muscle. D. Cardiac muscle has a shorter refractory period than skeletal muscle.
A
The cells of the myocardium behave as a single, coordinated unit called a: pacemaker functional syncytium sarcomere contractile unit
B
The primary role of the atrioventricular node (AV node) is to: A. contract a functional syncytium B. slow down impulses so that the atria can contract to fill adjacent ventricles with blood C. maintain the same speed of contraction from atria to ventricle D. transfer the pacemaker from the SA node E. create a second source of pace-making within the heart
B
The second heart sound, described as "dupp" is the sound of the: A. ventricles contracting B. semilunar valves closing C. atrioventricular valves closing D. heart slapping the liver
B
The sinoatrial node: A. Has no stable resting membrane potential B. Acts has the pacemaker in a normal healthy heart C. Has fast Ca++ channels open during the depolarization phase D. Has K+ channels open during the repolarization phase E. All of the above are correct statements
B
The vessels that carry oxygen to the myocardium are called: pulmonary arteries coronary arteries aortic arteries pulmonary veins
B
Ventricular relaxation immediately follows ________. A. ventricular depolarization B. ventricular repolarization C. atrial depolarization D. atrial repolarization
B
Which of the following lists the valves in the order through which the blood flows from the vena cava through the heart? A. Bicuspid, aortic semilunar, tricuspid, pulmonary semilunar B. Tricuspid, pulmonary semilunar, bicuspid, aortic semilunar C. Mitral, pulmonary semilunar, bicuspid, aortic semilunar D. Aortic semilunar, pulmonary semilunar, tricuspid, bicuspid
B
During the period of ejection in the cardiac cycle, the atrioventricular valves are _____ and the semilunar valves are __________. A. closed, closed B. open, open C. closed, open D. open, closed
C
Excess K+ ions in cardiac tissue cause heart rate and stroke volume to __________. increase I have no idea decrease remain the same
C
Freshly oxygenated blood is delivered to the ____________ and then it passes to the ____________, to be pumped to the entire body. right atrium, left ventricle left atrium, right ventricle left atrium, left ventricle right atrium, right ventricle
C
Preload: if increased, causes a decrease in cardiac output. is part of the extrinsic regulation of the heart. is the extent to which the ventricular walls are stretched. is the pressure in the aorta which contracting ventricles must overcome.
C
When the mitral valve closes, it prevents the backflow of blood from the: right atrium into the right ventricle left ventricle into the aorta left ventricle into the left atrium right ventricle into the pulmonary trunk
C
Action potentials pass rapidly from one cardiac muscle cell to another because of: A. open Ca++ channels B. the large voltage of cardiac action potentials. C. large nerves with branches going to each cardiac muscle cell. D. intercalated disks and numerous gap junctions. E. the plateau phase of the action potential.
D
If blood pH decreases and blood carbon dioxide increases: A. stroke volume decreases. B. heart rate increases. C. the change is detected by baroreceptors in the pulmonary arteries. D. all of these occur when pH and CO2 change
D
In an EKG, the P wave represents: repolarization of the atria. repolarization of the ventricles. depolarization of the ventricles. depolarization of the atria.
D
The cardiovascular centers are located in which area of the brain? mesencephalon (midbrain) cerebrum pons medulla oblongata
D
The tricuspid valve is located between the: right ventricle and the aorta right and left atria left atrium and left ventricle right atrium and right ventricle
D
What are attached directly to the leaflets or flaps of the atrioventricular valves (AV)? Trabecula carneae Pectinate muscles Papillary muscles Chordae tendinea
D
Which of the following factors gives the myocardium its high resistance to fatigue? A. The coronary circulation B. Gap junctions C. The presence of intercalated discs D. A very large number of mitochondria in the cytoplasm
D
Which portion of the ECG corresponds to repolarization of the atria? A. P wave B. QRS complex C. T wave D. none of the above: atrial repolarization is masked by ventricular depolarization
D
Increased sympathetic stimulation of the heart: increases the force of ventricular contraction opens a larger number of calcium slow channels increases the heart rate increase cardiac output all of the above
E
Increased venous return to the heart causes: A. ↑ stroke volume B. ↑ preload C. ↑ cardiac output D. ↑ force of contraction E. all of the above
E
