heart chp 21 masterings
Which of the following is NOT a reason that the fibrous skeleton of the heart is beneficial to the heart's function? It connects the heart to the lungs for greater stability in the thoracic cavity. It generates an elastic quality that helps the heart resume its normal shape after a contraction. It separates atrial cells from ventricular cells so that contractions can be coordinated. It provides physical support for the muscle cells, blood vessels, and nerves of the heart.
It connects the heart to the lungs for greater stability in the thoracic cavity.
Which of the following events would occur if the heart ceased to function? Pressure gradients within the pulmonary and systemic circuits would be unaffected. Mitochondria throughout the body would cease to produce normal levels of ATP because of the lack of oxygen and the accumulation of carbon dioxide. White blood cells would more easily be able to reach injured areas. All of the listed events would occur.
Mitochondria throughout the body would cease to produce normal levels of ATP because of the lack of oxygen and the accumulation of carbon dioxide.
Damage to the internodal pathways would NOT affect the function of the __________. AV node Purkinje fibers AV bundle SA node
SA node because the internodal pathways connect the SA to the AV and the rest of these are in the AV
In the pulmonary circuit, __________. body tissues receive oxygenated blood before the blood returns to the right atrium of the heart arteries carry deoxygenated blood to the lungs arteries carry oxygenated blood to the lungs veins carry deoxygenated blood to the lungs
arteries carry deoxygenated blood to the lungs
the structure that slows the electrical impulses arriving from the internodal pathways and thus allows the atria to complete their contraction prior to initiation of ventricular contraction?
atrioventricular node
The sinoatrial and atrioventricular nodes __________. establish cycles of contraction and relaxation for the myocardium transport electrical signals to the myocardium respond, like skeletal muscles, to ACh released from the sympathetic nervous system undergo powerful contractions as they force blood through the heart
establish cycles of contraction and relaxation for the myocardium
In comparison, the right atrium and ventricle __________. generate less pressure for contraction than the left atrium and ventricle are separated from the left atrium and ventricle by the coronary sulcus lie more posteriorly than the left atrium and ventricle have a larger volume than the left atrium and ventricle
generate less pressure for contraction than the left atrium and ventricle
Oxygenated blood returns to the heart from the lungs and enters the __________. right atrium right ventricle left atrium left ventricle
left atrium
When blood leaves the lungs and returns to the heart, it enters the __________. left atrium left ventricle right atrium right ventricle
left atrium
Damage to the mitral valve would allow the flow of blood into the __________. right atrium left ventricle right ventricle left atrium
left atrium (blood goes from atrium to ventricle so u dont want it to flow back because that would be damage)
Plaque buildup in the left coronary artery (LCA) would NOT affect which portion of the heart? left ventricle right atrium right ventricle left atrium
right atrium
A blockage in the pulmonary trunk would first affect which heart chamber with a buildup of blood? right atrium left atrium right ventricle left ventricle
right ventricle
The coronary sulcus __________. is filled with blood vessels that carry blood to and from the lungs separates the atria from the ventricles on the surface of the heart separates the right and left atria is found at the apex of the heart
separates the atria from the ventricles on the surface of the heart
The largest heart vein that returns deoxygenated blood from the arms to the right atrium is the __________. aorta coronary sinus superior vena cava inferior vena cava
superior vena cava
If a disease were to cause the corrosion of the fibrous skeleton of the heart, which of the following would NOT be affected? the forces experienced by the aorta as it received blood from the heart the positioning of blood vessels supplying blood to the heart muscle the arrangement of the striations of the tissue the coordination of contractions between the atria and the ventricles
the arrangement of the striations of the tissue
Which two chambers of the heart are connected by an opening during embryonic development that seals up at birth? the right atrium and right ventricle the left atrium and left ventricle the right and left atria the right and left ventricles
the right and left atria this is fossa ovalis
During which phase of the cardiac cycle would you find the atria empty? ventricular diastole atrial diastole ventricular systole atrial systole
ventricular systole
Which portion of the conducting system directly stimulates the ventricles? internodal pathways Purkinje fibers AV node bundle branches
Purkinje Fiber (these go to the ventricles)
Which of the following statements is FALSE regarding the differences between cardiac and skeletal muscle? Cardiac muscle is autorhythmic and involuntary in that it does not require stimulation from the nervous system and it sets its own pace. Cardiac muscle has a greater circulatory supply than skeletal muscle. Cardiac muscle can survive for a longer time in anaerobic conditions than skeletal muscle. Skeletal muscles have formed triads, whereas cardiac muscles do not.
Cardiac muscle can survive for a longer time in anaerobic conditions than skeletal muscle.