*Cardiovascular: HEART*

Question 1

What structures are found in the mediastinum?

Answer 1

Esophagus, heart, thymus gland, and trachea

Question 2

The heart lies obliquely in the mediastinum.

Answer 2

True

Question 3

The epicardium:

Answer 3

Is the visceral pericardium.

Question 4

The heart valves have a double layer of ________ with a layer of ________ in between.

Answer 4

Endocardium; connective tissue

Question 5

Musculi pectinati are found in the __________ ; trabeculae carneae are found in the __________ .

Answer 5

Auricles; Ventricles

Question 6

What structure delivers blood to the left atrium?

Answer 6

Pulmonary Veins

Question 7

The anterior interventricular artery is a branch of the:

Answer 7

left coronary artery

Question 8

The valve located between the left atrium and left ventricle is the:

Answer 8

Bicuspid (mitral) valve

Question 9

Strong connective tissue strings that are attached to papillary muscles and to the cusps of the atrioventricular valves are:

Answer 9

Chordae Tendinease

Question 10

Arrange them in the order in which an erythrocyte would pass through them after returning to the heart from the left arm.

1. aortic semilunar valve
2. bicuspid (mitral) valve
3. pulmonary semilunar valve
4. tricuspid valve.

Answer 10

4,3,2,1

4. Tricuspid Valve
5. Pulmonary semilunar valve
6. Bicuspid Valve
7. Aortic semilunar valve

Question 11

The skeleton of the heart:

Answer 11

electrically insulates the atria from the ventricles.

Question 12

what are the structures present in cardiac muscle cells?

Answer 12

• Desmosomes
• Gap junctions
• Smooth Sarcoplasmic Reticulum
• Transverse (T) tubules

Question 13

The group of modified cardiac muscle cells that delays action potentials between the atria and the atrioventricular bundle is called the:

Answer 13

AV node

Question 14

If the SA node becomes damaged and nonfunctional, which of these is the most likely to occur?

Answer 14

Another part of the heart, possibly the AV node, will become the pacemaker.

Question 15

Cardiac muscle has a prolonged period of slow repolarization called the plateau phase.

Answer 15

True

Question 16

Action potentials pass rapidly from one cardiac muscle cell to another because of:

Answer 16

intercalated disks and numerous gap junctions.

Question 17

The depolarization phase of the cardiac muscle action potential occurs when:

Answer 17

voltage-gated Na+ ion channels open.

Question 18

Early repolarization of cardiac muscle cells occurs when:

Answer 18

• Voltage-gated K+ ion channels open

- Voltage-gated Na+ ion channels open

Question 19

Which of these conditions occur in the cardiac muscle cell during the plateau phase?

Answer 19

• Voltage gated Ca2+ ion channels are open
• Voltage-gated K+ ion channels are open
• Voltage-gated Na+ ion channels are open

Question 20

Unlike other cardiac muscle cells, the movement of ____ into the pacemaker cells is primarily responsible for the depolarization phase of the action potential.

Answer 20

Ca2+ ions

Question 21

Which of these conditions results in a prepotential in pacemaker cells?

Answer 21

Na+ ions move into the cell through specialized Na+ ion channels.

Question 22

In an EKG, the P wave represents:

Answer 22

depolarization of the atria

Question 23

During the QT interval of the EKG, the:

Answer 23

ventricles contract and being to relax

Question 24

what condition is most likely to cause bradycardia?

Answer 24

excessive parasympathetic stimulation

Question 25

During the period of ejection in the cardiac cycle, the atrioventricular valves are __________ and the semilunar valves are __________ .

Answer 25

closed; open

Question 26

Blood flows neither into nor out of the ventricles during:

Answer 26

- The period of isovolumic contraction | - The period of isovolumic relaxation

Question 27

At the end of __________ , the ventricles are 70% filled.

Answer 27

Passive ventricular filling

Question 28

The average end-diastolic volume of the ventricles is about __________ , whereas the end-systolic volume is about __________ .

Answer 28

125 mL, 55 mL

Question 29

During the period of ejection, the left ventricular pressure reaches a high point of approximately

Answer 29

120 mm hg

Question 30

The second heart sound, described as "dupp" is actually the sound of the:

Answer 30

semilunar valves closing.

Question 31

If the heart rate for a patient is 80 bpm, and her stroke volume is 70 mL/beat, then her cardiac output is:

Answer 31

5600 mL/min

Question 32

Preload:

Answer 32

Is the extent to which the ventricular walls are stretched.

Question 33

Increased venous return to the heart causes increased:

Answer 33

- stroke volume - Preload - Cardiac Output - Force of contraction

Question 34

Parasympathetic nerve fibers:

Answer 34

Extend to terminal ganglia within the wall of the heart

Question 35

When normal arterial blood pressure decreases, baroreceptors cause a response that

Answer 35

returns blood pressure to normal

Question 36

If blood pH decreases and blood carbon dioxide increases:

Answer 36

heart rate increases

Question 37

increased sympathetic stimulation of the heart:

Answer 37

- increases the force of ventricular contraction - opens a larger number of calcium slow channels - increases the heart rate - increases cardiac output

Question 38

Generally, an increase in extracellular Ca2+ ions causes __________ force of contraction, and __________ heart rate.

Answer 38

increased; decreased

Question 39

Excess K+ ions in cardiac tissue cause heart rate and stroke volume to __________ and decreased extracellular K+ ions result in a __________ in heart rate.

Answer 39

Decrease; decrease