Chapter 19 openstax

Which of the following is not important in preventing

backflow of blood?

a. chordae tendineae

b. papillary muscles

c. AV valves

d. endocardium

D. Endocardium

Which valve separates the left atrium from the left

ventricle?

a. mitral

b. tricuspid

c. pulmonary

d. aortic

a. mitral/bicuspid

Which of the following lists the valves in the order

through which the blood flows from the vena cava through

the heart?

a. tricuspid, pulmonary semilunar, bicuspid, aortic

semilunar

b. mitral, pulmonary semilunar, bicuspid, aortic

semilunar

c. aortic semilunar, pulmonary semilunar, tricuspid,

bicuspid

d. bicuspid, aortic semilunar, tricuspid, pulmonary

semilunar

a. tricuspid, pulmonary semilunar, bicuspid, aortic semilunar

Which chamber initially receives blood from the

systemic circuit?

a. left atrium

b. left ventricle

c. right atrium

d. right ventricle

c. right atrium

The ________ layer secretes chemicals that help to

regulate ionic environments and strength of contraction and

serve as powerful vasoconstrictors.

a. pericardial sac

b. endocardium

c. myocardium

d. epicardium

b. endocardium

The myocardium would be the thickest in the ________.

a. left atrium

b. left ventricle

c. right atrium

d. right ventricle

b. left ventricle

In which septum is it normal to find openings in the

adult?

a. interatrial septum

b. interventricular septum

c. atrioventricular septum

d. all of the above

c. atrioventricular septum

Which of the following is unique to cardiac muscle

cells?

a. Only cardiac muscle contains a sarcoplasmic

reticulum.

b. Only cardiac muscle has gap junctions.

c. Only cardiac muscle is capable of

autorhythmicity

d. Only cardiac muscle has a high concentration of

mitochondria

c. only cardiac muscle is capable of autorhythmicity.

The influx of which ion accounts for the plateau phase?

a. sodium

b. potassium

c. chloride

d. calcium

d. calcium

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. none of the above: atrial repolarization is masked by ventricular depolarization.

Which component of the heart conduction system

would have the slowest rate of firing?

a. atrioventricular node

b. atrioventricular bundle

c. bundle branches

d. Purkinje fibers

d. purkinje fibers

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. systole

b. diastole

c. quiescent

d. isovolumic contraction

d. isovolumic contraction

Most blood enters the ventricle during ________.

a. atrial systole

b. atrial diastole

c. ventricular systole

d. isovolumic contraction

b. atrial diastole

The first heart sound represents which portion of the

cardiac cycle?

a. atrial systole

b. ventricular systole

c. closing of the atrioventricular valves

d. closing of the semilunar valves

c. closing of the atrioventricular valves

Ventricular relaxation immediately follows ________.

a. atrial depolarization

b. ventricular repolarization

c. ventricular depolarization

d. atrial repolarization

b. ventricular repolarization

The force the heart must overcome to pump blood is

known as ________.

a. preload

b. afterload

c. cardiac output

d. stroke volume

b. afterload

The cardiovascular centers are located in which area of

the brain?

a. medulla oblongata

b. pons

c. mesencephalon (midbrain)

d. cerebrum

a. medulla oblongata

In a healthy young adult, what happens to cardiac

output when heart rate increases above 160 bpm?

a. It increases.

b. It decreases.

c. It remains constant.

d. There is no way to predict.

b. it decreases

What happens to preload when there is venous

constriction in the veins?

a. It increases.

b. It decreases.

c. It remains constant.

d. There is no way to predict

a. it increases

Which of the following is a positive inotrope?

a. Na+

b. K

+

c. Ca2+

d. both Na+

and K+

c. Ca2+

The earliest organ to form and begin function within

the developing human is the ________.

a. brain

b. stomach

c. lungs

d. heart

d. heart

Of the three germ layers that give rise to all adult

tissues and organs, which gives rise to the heart?

a. ectoderm

b. endoderm

c. mesoderm

d. placenta

c. mesoderm

The two tubes that eventually fuse to form the heart are

referred to as the ________.

a. primitive heart tubes

b. endocardial tubes

c. cardiogenic region

d. cardiogenic tubes

d. cardiogenic tubes

Which primitive area of the heart will give rise to the

right ventricle?

a. bulbus cordis

b. primitive ventricle

c. sinus venosus

d. truncus arteriosus

a. bulbus cordis

The pulmonary trunk and aorta are derived from which

primitive heart structure?

a. bulbus cordis

b. primitive ventricle

c. sinus venosus

d. truncus arteriosus

d. truncus arteriosus