chapter 18 study questions
the fact that the left ventricle of the heart is thicker than the right ventricle reveals that it _____ A) pumps a greater volume of blood B) pumps blood against a greater resistance C) expands the thoracic cage D) sends blood through a smaller valve
pumps blood against a greater resistance
the receiving chambers of the heart include the ______ A) right and left atria B) right and left ventricles C) right atrium and ventricle D) left atrium and ventricle
right and left atria
the AV valves are closed A) when the ventricles are in diastole B) when the ventricles are in systole C) while the atria are contracting D) by the movement of blood from atria to ventricles
when the ventricles are in systole
the foramen ovale ________ A) connected the two atria in the fetal heart B) is a condition in which the heart valves do not completely close C) is a shallow depression in the interventricular septum D) is a connection between the pulmonary trunk and the aorta in the fetus
connected the two atria in the fetal heart
the source of blood carried to capillaries in the myocardium would be the ______ A) coronary sinus B) fossa ovalis C) coronary arteries D) coronary veins
coronary arteries
if cardiac muscle is deprived of its normal blood supply, damage would primarily result from _____ A) decreased delivery of oxygen B) a decrease in the number of available mitochondria for energy production C) a lack of nutrients to feed into metabolic pathways D) an inadequate supply of lactic acid
decreased delivery of oxygen
the inner lining of the heart A) Parietal layer B) Epicardium C) Endocardium D) Myocardium
endocardium
serous layer covering the heart muscle A) Parietal layer B) Epicardium C) Endocardium D) Myocardium
epicardium
compared to skeletal muscle, cardiac muscle ______ A) has gap junctions that allow it to act as a functional syncytium B) lacks striations C) has more nuclei per cell D) cells are larger than skeletal muscle cells
has gap junctions that allow it to act as a functional syncytium
the heart if called a "double pump" because there are two functionally separate circulations. trace the pathway of each of these circulations and include the following information: heart chambers involved, major blood vessels involved, and general areas through which the blood flows. begin with the right atrium
inferior vena cava > superior vena cava > right atrium > tricuspid valve > right ventricle > pulmonary valve > pulmonary artery > lungs > pulmonary vein > left atrium > mitral valve > left ventricle > aortic valve > aorta
which chambers of the heart contain oxygenated blood? A) right and left atria B) right and left ventricles C) right atrium and ventricle D) left atrium and ventricle
left atrium and ventricle
the parietal pericardium ______ A) lines the internal surface of the fibrous pericardium B) is also called the epicardium C) is separated from the fibrous pericardium by serous fluid D) is found within the pericardial cavity
lines the internal surface of the fibrous pericardium
atrioventricular (AV) valve with TWO flaps A) Aortic semilunar valve B) Mitral (bicuspid) valve C) Pulmonary semilunar valve D) Tricuspid valve
mitral (bicuspid) valve
prevents backflow into the left atrium A) Aortic semilunar valve B) Mitral (bicuspid) valve C) Pulmonary semilunar valve D) Tricuspid valve
mitral (bicuspid) valve
heart muscle A) Parietal layer B) Epicardium C) Endocardium D) Myocardium
myocardium
the outermost layer of the serous pericardium A) Parietal layer B) Epicardium C) Endocardium D) Myocardium
parietal layer
exercise results in skeletal muscles compressing veins which encourages blood to return to the heart. in this scenario, which of the following is correct? A) preload increases B) stroke volume decreases C) venous return decreases D) end diastolic volume (EDV) decreases
preload increases
prevents backflow into the right ventricle A) Aortic semilunar valve B) Mitral (bicuspid) valve C) Pulmonary semilunar valve D) Tricuspid valve
pulmonary semilunar valve
which vessel (s) of the heart receive (s) blood from the right ventricle? A) venae cavae B) pulmonary trunk C) aorta D) pulmonary veins
pulmonary trunk
which is NOT a vessel that brings blood directly into the right atrium? A) superior vena cava B) inferior vena cava C) pulmonary vein D) coronary sinus
pulmonary vein
the left ventricular wall of the heart is thicker than the right wall in order to _____ A) accommodate a greater volume of blood B) expand the thoracic cage during diastole C) pump blood with greater pressure D) pump blood through a smaller valve
pump blood with greater pressure
prevents backflow into the left ventricle A) Aortic semilunar valve B) Mitral (bicuspid) valve C) Pulmonary semilunar valve D) Tricuspid valve
aortic semilunar valve
what is the difference between the auricles and the atria?
atria are the upper chambers of the heart, whereas auricles are small appendages that make rough interior parts of the atria. the function of the atrium is to receive the blood into the heart and pass it into the ventricles in order to complete circulation cycles. the function of auricles is to increase the blood-holding capacity of atria.
pectinate muscles are found in the ______ A) atria only B) atria and ventricles C) ventricles only D) right atrium and right ventricle only
atria only
if the mitral valve is unable to close properly, ______ A) blood could flow back into the left atrium B) blood could flow back into the left ventricle C) blood could flow back into the right atrium D) blood could flow back into the right ventricle
blood could flow back into the left atrium
select the correct statement about the heart valves A) The mitral (bicuspid) valve separates the right atrium from the right ventricle. B) The tricuspid valve divides the left atrium from the left ventricle. C) Aortic and pulmonary semilunar valves control the flow of blood into the heart. D) The atrioventricular (AV) valves prevent backflow of blood added into the atria during ventricular contraction.
the AV valves prevent backflow of blood added into the atria during ventricular contraction
select the correct statement about the function of myocardial cells A) The entire heart contracts as a unit or it does not contract at all. B) Cardiac muscle cells are innervated by sympathetic, parasympathetic, and somatic nerve fibers so that the nervous system can increase heart rate. C) The refractory period in skeletal muscle is much longer than that in cardiac muscle. D) The influx of potassium ions from extracellular sources is the initiating event in cardiac muscle contraction.
the entire heart contracts as a unit or it does not contract at all
if the vagal nerves to the heart were cut, the result would be that _____ A) the heart would stop, since the vagal nerves trigger the heart to contract B) the heart rate would increase by about 25 beats per minute C) the atrioventricular (AV) node would become the pacemaker of the heart D) parasympathetic stimulation would increase, causing a decrease in heart rate
the heart rate would increase by about 25 bpm
select the correct statement about the structure of the heart wall A) The fibrous cardiac skeleton forms the bulk of the heart. B) Connective tissue in the heart wall aids in the conduction of the action potential. C) The heart chambers are lined by the endomysium. D) The myocardium is the layer of the heart that actually contracts.
the myocardium is the layer of the heart that actually contracts
list the three vessels that bring oxygen-poor blood to the right atrium. which regions of the body do they serve?
the superior vena cava returns oxygen-poor blood from body regions superior to the diaphragm. the inferior vena cava returns oxygen-poor blood from body areas inferior to the diaphragm. the coronary sinus collects blood draining from the myocardium
which of the following is NOT an age-related change affecting the heart? A) atherosclerosis B) decline in cardiac reserve C) fibrosis of cardiac muscle D) thinning of the valve flaps
thinning of the valve flaps
atrioventricular (AV) valve with THREE flaps A) Aortic semilunar valve B) Mitral (bicuspid) valve C) Pulmonary semilunar valve D) Tricuspid valve
tricuspid valve
prevents backflow into the right atrium A) Aortic semilunar valve B) Mitral (bicuspid) valve C) Pulmonary semilunar valve D) Tricuspid valve
tricuspid valve