Week 3 - Heart

Question 1

The heart is located in the ______ along with what structures?

Answer 1

mediastinum

esophagus, aorta

Question 2

The function of fibrous pericardium is _______

Answer 2

protect & anchor HT, prevent overstretching

Question 3

The function of serous pericardium is _______

Answer 3

prevent friction between contracting HT and fibrous pericardium

Question 4

List and describe layers of the heart from exterior to interior

Answer 4

epicardium - visceral layer of serous pericardium
myocardium - cardiac muscle layer
endocardium - chamber lining & valves

Question 5

The blood from right ventricle goes to the _______

Answer 5

pulmonary trunk -> right and left pulmonary arteries

Question 6

The bicuspid valve is also known as _______

Answer 6

mitral valve

Question 7

The _______ muscles attach to the atrioventricular valves via the __________ and contract to prevent inversion or prolapse of these valves

Answer 7

papillary

chordae tendineae

Question 8

The foramen ovalis is ________

Answer 8

in developing fetus an opening in right atrium where blood bypasses the right ventricle and directly enters the left atrium

Question 9

The ductus arteriosus is _________

Answer 9

in developing fetus a blood vessel connecting the pulmonary artery to the proximal descending aorta, bypassing the lungs

Question 10

The fibrous skeleton of heart is composed of ________. Its functions are ________

Answer 10

dense connective tissue rings
support structure for heart valves
insertion point for cardiac muscle bundles
electrical insulator between atria and ventricles

Question 11

Describe systemic blood circulation

Answer 11

left ventricle pumps oxygenated blood into aorta
aorta branches into many arteries that travel to organs
arteries branch into arterioles in tissue
arterioles branch into capillaries
deoxygenated blood begins return into venules
venules merge into veins and return to right atrium

Question 12

Describe pulmonary blood circulation

Answer 12

right side of HT pumps deoxygenated blood to LU
right ventricle pumps blood to pulmonary trunk
pulmonary trunk branches into pulmonary arteries
pulmonary arteries carry blood to LU for exchange of gases
oxygenated blood returns to HT in pulmonary veins

Question 13

Anastomoses are _______

Answer 13

connections between arteries supplying blood to the same region, providing alternate routes if one artery become occluded

Question 14

Describe conduction system of HT

Answer 14

SA Node - cluster of autorhthymic cells in right atrium begins HT activity that spreads to both atria, excitation spreads to AV node
AV node transmits signal to AV bundle of His
AV bundle divides into right & left bundle branches & purkinje fibers

Question 15

SA node fires spontaneously ____ times per minute

AV node fires at ______ times per minute

Answer 15

60-100

40-60

Question 16

Ectopic pacemakers are _____ and can be caused by stimulants including _____

Answer 16

extra beats forming at other sites of the HT

caffeine, nicotine

Question 17

In an electrocardiogram, the P wave denotes _____ while the QRS complex denotes ________

Answer 17

atrial depolarization

ventricular depolarization

Question 18

In the normal cardiac cycle, the End diastolic volume (EDV) is about ___ml while the End systolic volume (ESV) is about ___ ml. The stroke volume is defined as ______

Answer 18

130 ml
60ml
EDV - ESV

Question 19

List the phases of the cardiac cycle

Answer 19

Isovolumetric relaxation
Ventricular filling
Atrial systole
Isovolumetric contraction
Ventricular systole

Question 20

In the cardiac cycle, isovolumetric relaxation is a brief period when volume in ventricle ________ as ventricles ______, pressure ____ and AV valves & semilunar valves are ______

Answer 20

does not change
relax
drops
closed

Question 21

In the cardiac cycle, ventricular filling is the period when _____

Answer 21

blood flows from full atria into ventricle
diastasis - blood trickles into ventricle
atrial systole - pumps final 20-25ml blood into ventricle

Question 22

In the cardiac cycle, isovolumetric contraction is the period when _____

Answer 22

atria, ventricles are all in contraction and AV/SL valves are closed

Question 23

In the cardiac cycle, ventricular systole is the period when ________

Answer 23

ventricles pump blood into pulmonary trunk / ascending aorta

Question 24

Cardiac output = ______

Answer 24

Stroke volume (SV) * Heart Rate (HR)

Question 25

Cardiac reserve = _____
In the average person, cardiac reserve is _____
In atheletes, cardiac reserve is _______

Answer 25

maximum output / output at rest
4-5
7-8

Question 26

List and define influences on Stroke Volume

Answer 26

Preload - affect of stretching
Contractility - force of contraction
Afterload - amount of pressure created by blood resisting flow

Question 27

In cardiac output, what can influence the Preload?

Answer 27

amount of stretching of cardiac muscle

Question 28

In cardiac output, what can influence contractility?

Answer 28

autonomic nerves, hormones, CA2+ or K+

Question 29

In cardiac output, what can influence afterload?

Answer 29

arterial blood pressure in diastole

Question 30

Heart rate is regulated by what part of the nervous system?

Answer 30

cardiovascular center in medulla oblongata

Question 31

The phase in the cardiac cycle when the mitral valve is closed and the aortic valve is open is the _______

Answer 31

systolic ejection phase

Question 32

The first heard sound (“lub”) is associated with the ____

Answer 32

closing of the AV valves

Question 33

An increase in the rate of action potentials from baroreceptors will reflexively lead to what change in heart rate? in blood pressure?

Answer 33

decrease

decrease