Heart Anatomy & Physiology
Action potentials pass from one cardiac muscle cell to another
a) through gap junctions
b) by a special cardiac nervous system
c) because of the large voltage of the action potentials
d) because of the plateau phase of the action potential
e) by neurotransmitters
a) through gap junctions
Which part of the heart's conducting system is known as the pacemaker of the heart?
A) Purkinje fibers
B) Internodal pathways
C) Sinoatrial node
D) Atrioventricular
(AV) node
C) Sinoatrial (SA) node
Comparing and contrasting arteries and veins, veins have
a) thicker walls
b) a greater amount of smooth muscle
c) a tunica media, but arteries do not
d) valves, but arteries do not
e) all of these are correct
d) valves, but arteries do not
The following describes what measurement on a blood pressure reading?
When pressure drops below normal flow (laminar blood flow), normal flow restored, and sounds disappear.
a) systolic
b) diastolic
b) diastolic
The second heart sound is caused by the
A) closing of the AV valves
B) closing of the semilunar valves
C) blood rushing out of the ventricles
D) filling of the ventricles
E) ventricle contraction
B) closing of the semilunar valves
Which layer of pericardium is equivalent to the epicardium?
a. parietal pericardium
b.pericardial sac
c. fibrous pericardium
d. visceral pericardium
d. visceral pericardium
During what phase do the AV valves close?
A) Atrial systole
B) Ventricular systole
C) Atrial diastole
D) Ventricular diastole
B) Ventricular systole
These type of capillaries have low permeability
a) contingent capillaries
b) fenestrated capillaries
c) continuous capillaries
d) sinusoidal capillaries
c) continuous capillaries
Why does blood pressure increase during exercise?
a) because heart rate increases
b) because of decreased sympathetic tone
c) because stroke volume increases
d) both A and C
d) both A and C
Why is there no wave corresponding to atrial repolarization on an ECG reading?
a) It is masked by the QRS complex.
b.Atrial repolarization produces no electrical effect at all.
c. It is masked by the P wave.
d.None of the above are correct.
a) It is masked by the QRS complex.
Why is the left ventricle more muscular than the right ventricle?
a) It pumps a smaller volume of blood.
b) It contracts with force sufficient to push blood through to systemic circulation.
c) The papillary muscles are stronger.
d) Both A and B are correct.
b. It contracts with force sufficient to push blood through to system circulation.
During ventricular systole of the cardiac cycle, all of the following would occur EXCEPT _____.
a.rising ventricular blood pressure would exceed aortic pressure
b.all heart valves would be closed
c.atrial diastole would occur as both the atria fill
d.pressure in ventricles would force the semilunar
valves closed
d. pressure in ventricles would force the semilunar
valves closed
These blood vessels have thick tunica media, a tunica intima with a well-developed internal elastic membrane, and thick tunica adventitia.
a) Elastic arteries
b) Medium & large veins
c) Arterioles
d) Muscular arteries
d) Muscular arteries
When blood flow decreases, resistance is _________ and blood pressure is _________________.
a) high, low
b) low, high
c) low, low
d) high, high
a) high, low
The hepatic portal system delivers _____.
a.nutrients to the liver
b.wastes to the kidneys
c.oxygenated blood to the abdominal organs
d.hormones and enzymes to the pancreas
a.nutrients to the liver
Dorothy was born with a malformed pulmonary valve. How will that affect her circulation?
a. Blood will flow more efficiently into her pulmonary trunk.
b. Blood will regurgitate into her right atrium.
c. Blood will flow back into her right ventricle.
d. Oxygenated blood will continuously pass around her pulmonary circuit.
c. Blood will flow back into her right ventricle.
Step in the cardiac conduction system: Impulse distributed by Purkinje fibers throughout ventricular myocardium; ventricular contraction completes.
What is the corresponding step as recorded on an ECG?
a) P wave: atrial depolarization
b) Q wave: beginning of ventricular depolarization
c) QRS complex: completion of ventricular depolarization
d) P-R interval: conduction of AV node and AV bundle
c) QRS complex: completion of ventricular depolarization
Put the following in the correct order (leaving the heart to entering the heart)
Arterioles
Muscular Arteries
Venules
Medium & large veins
Elastic Arteries
Small Veins
1) Elastic arteries
2) Muscular arteries
3) Arterioles
4) Capillaries
5) Venules
6) Medium & large veins (e.g. superior & inferior vena cava)
When blood oxygen levels markedly decrease, the chemoreceptor reflex causes:
a) peripheral resistance to decrease
b) mean arterial blood pressure to increase
c) vasomotor tone to decrease
d) vasodilation
e) all of these are correct
b) mean arterial blood pressure to increase
What event is happening if net filtration pressure (NFP) is negative?
a.Fluid is moving out of a capillary.
b.The volume of interstitial fluid is increasing.
c.Reabsorption is occurring in a capillary.
d.The person may be hemorrhaging.
c. Reabsorption is occurring in a capillary.
The Starling law of the heart states that the greater the stretch of ventricular walls, the greater the force of contraction. This amount stretch is also known as
A) Afterload
B) Preload
C) Mean arterial pressure
D) Peripheral resistance
B) Preload
What causes the plateau phase in cardiac muscle cells?
Some voltage-gated K+ channels open, causing early repolarization.
Ca2+ channels are open, producing the plateau and slowing further repolarization.
List places on the body where a pulse can be taken.
Superficial temporal artery
Common carotid artery
Facial artery
Radial artery
Axillary artery
Popliteal artery
Brachial artery
Femoral artery
Dorsalis pedis artery
Posterior tibial artery
Fill in the blank, choose the correct option:
At the arterial end of capillary bed, _______________ pressure is positive because the __________________ pressure is (greater/less) than the net osmotic pressure.
More fluid moves (out of/into)the capillary.
At the arterial end of capillary bed, net filtration pressure is positive because the hydrostatic pressure is greater than the net osmotic pressure.
More fluid moves out of the capillary.
Name and summarize mechanisms that regulate blood pressure on a long-term basis.
1) Renin-Angiotensin-Aldosterone Mechanism: hormonal mechanism that regulates blood pressure by altering blood volume. Involves kidneys, adrenal glands, and lungs.
2) Antidiuretic Hormone (Vasopressin) Mechanism: hormonal mechanism that involves the baroreceptors and releasing ADH in order to increase blood pressure.
3) Atrial Natriuretic Mechanism: hormonal mechanism where, in response to higher venous return, cells in the atria release ANH in order to decrease blood pressure and increase urine volume
4) Fluid shift mechanism: activated by changes in pressure across the capillary walls. Increase in BP, fluid moves into interstitial space, drop in BP. Decrease in BP, fluid moves into capillaries, increase in BP.
5) Stress-relaxation response: Smooth muscle response (contraction or relaxation) in responses to changes in blood pressure.