anatomy chapter 22 (heart)
Another name for the visceral layer of the serous pericardium is ________________.
epicardium
Which bears a close structural relationship with the fossa ovalis?
foramen ovale
T/F About seventy percent of the ventricle filling is achieved passively without the contraction of the atria.
true
T/F All cardiac veins eventually drain into the coronary sinus for return of the blood from the myocardium to the right atrium.
true
T/F All of the heart's sulci house blood vessels that supply the myocardium.
true
T/F It is during weeks 5-8 that the single heart tube of the embryo becomes partitioned into four chambers and the main vessels that leave and enter the heart form.
true
T/F It is the contraction of the atria during atrial systole that completes the filling of the ventricles while the ventricles are in diastole.
true
T/F Like the right atrium, the left atrium has pectinate muscles along its anterior wall.
true
T/F No matter the cause, hypertrophy of the heart causes it to work less efficiently.
true
T/F Normal passage of blood from the atria to the ventricles only happens if the atrioventricular valves are open.
true
T/F One reason that necessitates the relatively early development of the heart is that the embryo has become too large to receive adequate nutrient supply by diffusion alone.
true
T/F Parasympathetic innervation decreases the heart rate, but generally tends to have no effect on the force of contractions.
true
T/F The embryonic heart actually begins working before its development is complete.
true
T/F The gap junctions of intercalated discs provide a low-resistance pathway across the membranes of adjoining cardiac muscle fibers.
true
T/F The left ventricle has a wall that is typically three times thicker than the right ventricular wall.
true
T/F The right and left coronary arteries are the only branches of the ascending aorta.
true
T/F Though the autonomic innervation by autonomic centers in the brainstem cannot initiate a heartbeat, it can increase or decrease the heart rate.
true
The _______________ cardiac vein travels alongside the right marginal artery.
small
During a cardiac cycle, how many of the four chambers contract at any one time?
2
How many half-moon shaped, pocketlike cusps are found in each semilunar valve?
3
Which values are reasonable for a healthy, 80 kilogram resting adult?
5.25 liters of blood pumped per ventricle per minute; 108,000 beats per day
Of the four "normal" heart sounds, the initial "lubb" sound is heard when the
AV valves close
Parasympathetic innervation of the heart occurs via
CN X
What part of the cardiac conduction system is located in the posterior wall of the right atrium, adjacent to the entrance of the superior vena cava?
SA node
Sympathetic innervation of the heart arises from the ________ segments of the spinal cord.
T1T5
Which describes the endocardium? a: Has single layer of epithelium b: Has layer of areolar connective tissue c: Epithelial cells are squamous d: Epithelial cells are cuboidal e: Has layer of adipose connective tissue f: Has patches of myocardium
a, b, c
Which are functions performed by the fibrous skeleton of the heart? a: Separates the atria and ventricles b: Anchors the heart valves c: Provides electrical insulation between the atria and ventricles d: Provides the framework for the attachment of the myocardium e: None of these are true functions of the fibrous skeleton of the heart.
a, b, c, d
Sympathetic innervation of the heart a: increases the heart rate. b: decreases the heart rate. c: increases the force of contractions. d: decreases the force of contractions. e: has no effect on contraction force.
a, c
Which are differences between cardiac muscle tissue and skeletal muscle tissue? a: The sarcoplasmic reticulum in cardiac muscle is less extensive. b: The sarcoplasmic reticulum in cardiac muscle is more organized. c: Cardiac muscle has intercalated discs; skeletal muscle does not. d: Cardiac muscle has 1 or 2 nuclei per cell; skeletal muscle has multiple nuclei per cell. e: Cardiac muscle has more well defined terminal cisternae.
a, c, d
Which can be used to characterize blood flow in the human body? a: There is a unidirectional blood flow. b: Arteries always carry oxygenated blood. c: Veins always carry deoxygenated blood. d: Arteries carry blood away from the heart. e: Veins carry blood toward the heart.
a, d, e
The cardiac cycle is
all the events involved with a single heart beat
The connections shared by arteries that allow them to shunt blood from one artery to another are called _________________.
anastomoses
The great cardiac vein runs alongside the
anterior interventricular artery
Which does not drain into the coronary sinus?
anterior interventricular vein
Pectinate muscles are found on the
anterior wall of the right and left atria
Which structure marks the end of the left ventricle and the entrance to the aorta?
aortic semilunar valve
Which valve prevents the backflow of blood into the left ventricle when the ventricles relax?
aortic semilunar valve
The inferior, conical end of the heart is called the _______________.
apex
It is the _____________ that permits the compression necessary to pump large volumes of blood out of the ventricles.
arrangement of cardiac muscle in the heart wall
The beginning of the cardiac cycle is when the
atria contract
In an EKG, the P wave is generated when the
atria depolarize
The anterior part of each atrium is a flaplike extension called a(n) _______________.
auricle
The property that allows the heart to initiate each heartbeat itself is called __________________.
autorhythmicity
The sequence of events in the transmission of an impulse through the heart muscle is a: AV node b: AV bundle c: SA node d: through the atria e: through the ventricles f: bundle branches g: Purkinje fibers
c, d, a, b, f, g, e
The papillary muscles attach to the cusps of the atrioventricular valves by means of the
chordae tendineae
During isovolumetric relaxation, the semilunar valves ________________.
close
The chordae tendineae are made out of
collagen fibers
Cardiac muscle fibers
contract as a single unit
Which action causes the closure of the right atrioventricular valve?
contraction of the right ventricle
The atria are separated from the ventricles externally by the
coronary sulcus
The left and right coronary arteries travel within the
coronary sulcus
The pulmonary arteries carry _______________ blood to the lungs.
deoxygenated
The numerous ________________ within the intercalated discs prevent cardiac muscle fibers from pulling apart.
desmosomes
During isovolumetric contraction, the atria are in
diastole
Most coronary blood flow occurs during ventricular ________________.
diastole
The relaxation phase of a heart chamber is termed ________________.
diastole
In an aging heart, increased flexibility of the heart valves may lead to a heart murmur.
false
T/F Because of the constant inflow of blood, the atria are thick-walled and located inferiorly in the heart.
false
T/F During ventricular contraction the semilunar valves close in order to permit the blood to enter the large arterial trunks that carry blood away from the heart.
false
T/F The relatively small size of the Purkinje fibers allows for the extremely rapid impulse conduction through the ventricles.
false
The foramen ovale is actually an opening in the
interatrial septum
The cell-to-cell contacts of the cardiac muscle fibers are called
intercalated discs
The term used to describe the inadequate blood flow to a structure caused by obstruction of the blood supply is _________________.
ischemia
Which analogy fits the human heart?
it is like a double pump, each working side by side with the other
The base of the heart is formed primarily by the
left atrium
The serous fluid within the pericardial cavity works to
lubricate the membranes of the serous pericardium
The trabeculae carneae in the left ventricle are ____________ in the right ventricle.
more prominent than
The layer of the heart wall composed of cardiac muscle tissue is the
myocardium
The middle layer of the heart wall that is made of cardiac muscle tissue is the ________________.
myocardium
For ___________ of the cardiac cycle, all four chambers are in diastole together.
one-half
The heartbeat is initiated by the cardiac muscle fibers of the _______________ node.
sinoatrial
The heart valves
permit the passage of blood in one direction
Which correctly describes the heart's apex?
projects slightly anteroinferiorly toward the left side of the body
The ______________ circuit consists of the chambers on the right side of the heart as well as the pulmonary arteries and veins.
pulmonary
Which of the cardiovascular system's circuits has deoxygenated blood in its arteries?
pulmonary circuit
Which carries oxygenated blood from the lungs to the heart?
pulmonary veins
As blood is pumped into the arterial trunks past the semilunar valves, it
pushes against the cusps, forcing the valves open
In an EKG, the T wave denotes
repolarization of the ventricles
Which heart chambers pump deoxygenated blood?
right atrium and right ventricle
Which pair is located more anteriorly in a heart in normal position?
right atrium and right ventricle
The right border of the heart is supplied by the
right marginal artery
________________ innervation increases the rate and the force of heart contraction.
sympathetic
The left atrium and left ventricle are part of which circuit of the cardiovascular system?
systemic circuit
Which circuit of the cardiovascular system is responsible for sending blood to the kidneys, stomach, and pelvic regions?
systemic circuit
Which may predispose one to inadequate coronary blood flow?
tachycardia
The function of the coronary sinus is to
take blood from the coronary circulation to the right atrium
During ventricular diastole
the semilunar valves close and the AV valves open
During ventricular systole
the semilunar valves open and the AV valves close
The arteries and veins that leave and enter the heart are called the great vessels because
they have relatively large diameters
Development of the heart commences in the _______ week.
third
The internal wall surface of each ventricle displays large, smooth, irregular muscular ridges called
trabeculae carneae
Which prenatal structure forms the ascending aorta and pulmonary trunk?
truncus arteriosus
Typically, there are __________ papillary muscles that project from the wall of the left ventricle and attach to the chordae tendineae that support the left AV valve.
two
The inferior chambers of the heart are called ________________.
ventricles
The inferior chambers of the heart are the
ventricles
One example of cardiac arrhythmia is _________, in which a rapid, repetitious movement of the ventricular muscle replaces normal contractions.
ventricular fibrillation
The epicardium is another name for the
visceral layer of the serous pericardium