Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIO 235 Final > Chapter 20: The Cardiovascular System: The Heart > Flashcards

Chapter 20: The Cardiovascular System: The Heart Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Where is the heart located?

A

It lies in the mediastinum, the anatomical region that extends from the sternum to the vertebral column, from the 1st rib to the diaphragm

It rests on the diaphragm near the midline of the thoracic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the apex and base of the heart

A

Apex is pointed and formed by the tip of the left ventricle

the base is its posterior aspect formed by the atria (upper chamber), mostly the left atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the anterior and inferior surface of the heart

A

Anterior - deep to the sternum and ribs

Inferior - part of the heart between the apex and right surface and rests mostly on the diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Differentiate between the right and left surfaces of the heart

A

Right - faces right lung and enters from inferior surface to base
Left - face left lung and extends from base to apex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define the pericardium and its 2 main parts

A

pericardium - membrane that surrounds and protects the heart

  1. Fibrous pericardium - tough, inelastic, dense irregular connective tissue that prevents overstitching, provides protections, and anchors the heart in the mediastinum
  2. Serous pericardium - deeper, thinner, delicate membrane that forms a double layer around the heart; outer parietal layer is fused to the fibrous pericardium and inner visceral layer aka epicardium adheres tightly to the heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define pericardial fluid

A

Thin film of lubriccating serous fluid between the parietal and visceral layers of the serous pericardium

It reduces friction as the heart moves and is located in the pericardial cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the 3 layers of the heart wall

A
  1. Epicardium (external layer) is composed of 2 tissue layers: outermost is the visceral layers of the serous pericardium composed of mesothelium; beneath is a variable layer of delicate fibroeslastic tissue and adipose tissue, thickest over ventricular surfaces
  2. Myocardium (middle) is responsible for the pumping action of the heart and is composed of cardiac muscle tissue and the fibers are composed of endomysium and perimysium and organized in bundles that swirl diagonally around the heart
  3. Endocardium (inner) is a thin layer of endothelium overlying a thin layer of connective tissue that provides a smooth lining for the chambers of the heart to minimize surface friction and covers the heart valves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

List the 4 chambers of the heart

A

The two superior receiving chambers are the atria and the two inferior pumping chambers are the ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define the auricle

A

A wrinkled pouch like structure on the anterior surface of each atrium that slightly increases the capacity of an atrium so that it can hold a greater volume of blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the significance of a sulcus?

A

Each sulcus marks the external boundary between two chambers of the heard - they are a series of grooves that contain coronary blood vessels and fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Coronary vs anterior interventricular sulcus vs posterior interventricular sulcus

A

Coronary - encircles most of the heart and marks the external boundary between the superior atria and inferior ventricles

anterior - shallow groove on the antihero surface that marks the external boundary between the right and left ventricles on the anterior aspect of the heart

posterior - marks external boundary between the ventricles on the posterior aspect of the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The right atrium receives blood from which 3 veins?

A

superiro vena cava, inferior vena cava, and coronary sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the following aspects of the right atrium: pectinate muscles, interatrial septum, fossa ovals, tricuspid valve

A

The anterior wall fo the atrium is rough due to pectinate muscles which are muscular ridges that extend into the auricle

Interatrial septum - a thin portion between the right and left atrium

Fossa ovalis - a oval depression in the septum, which is a remanent of the foramen oval, an opening in the septum that closes soon after birth

tricuspid valve - blood passes from the right atrium to the right ventricle through this valve that consists of 3 cusps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the following components of the right ventricle: trabecular carneae, chordae tendineae, papillary muscles, inter-ventricular septum, pulmonary valve

A

Trabecular carneae - cardiac muscle fibers that form a series of ridges inside the ventricle

Chordae tendineae - cords connected to the tricuspid valve which are intern connected to a cone-shaped trabeculae cornea called papillary muscles

Interventricular septum - suppurates the right and left ventricle

Pulmonary valve - blood passes from right valve into a large artery called the pulmonary trunk which divides into the right and left pulmonary arteries and caries blood to the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does blood flow in and out of the left atrium?

A

Received blood from the lungs via the pulmonary veins and passes into the left ventricle via the bicuspid (mitral) valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the left ventricle and its following components: aortic valve, ligaments arteriorsum

A

The left ventricle is the thickest chamber and forms the apex of the heart

Blood passes from the left ventricle through the aortic valve into the ascending aorta - some flow into coronary arteries and the remained passes into the arch of the aorta and descending aorta where it is carried throughout the body

Ligamentum arteriosum - connects the arch of the aorta and pulmonary trunk and is the remanent of the ductus arteriosus that closes shortly after birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does myocardial thickness relate to its function?

A

Ventricles pump blood under higher pressure and thus are thicker

Additionally, the left has a much larger workload as it must pump blood throughout the body and thus is thicker than the right

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the fibrous skeleton of the heart?

A

The fibrous skeletal consists of four dense connective tissue rings that surround the valves of heart, fuse with one another, and merge with the interventricular septum

This is in addition to cardiac muscle tissue and prevents overstitching of the valves and serves asa point of insertion for bundles of cardia muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the operation of the atrioventricular valves (AV)

A

The AV include the tricupsid and bicuspid valve

When ventricles are relaxes, papillary muscles are relaxed, chordae tendineae are slack, and blood moves from a higher pressure in the atria to a lower pressure in the ventricles through open AV valves

When ventricles contract, the blood drives the cusps upward until their edges meet and close the opening

If AV valves or chordae tendinaea are damaged, blood may regurgitate (flow back( into the atria when ventricles contract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the operations of the semilunar valves (SV)

A

SV are in both the aortic and pulmonary valves because they are made up of 3 crescent moon-shaped cusps

Each cusp attaches to the arterial wall by its convex outer margin and they allow ejection of blood from heart into arteries but prevent bacflow into the ventricles

When ventricles contract, pressure builds up and the SL valves open when pressure in the ventricles exceeds pressure in the arteries, permitting ejection of blood from the ventricles into the pulmonary trunk and aorta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the difference between systemic and pulmonary circulations?

A

The left side of the heart is the pump for systemic circulation - it receives red oxygenated blood from the lungs and the ventricle elects blood into aorta and carries it throughout the body here it looses O2 and gains CO2

The right side of the heart is the pump for pulmonary circulation - it receives all of the dark-red deoxygenated blood returning and the blood is ejected from the right ventricle into the pulmonary arteries were it is is taken to the lungs to be exhaled and picks up O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the major features of coronary circulation

A

Coronary circulation - myocardium’s own network of blood vessels as nutrients cannot diffuse quickly enough from blood

Coronary arteries branch from the ascending aorta and encircle the heart and while the heart is contracting there is little blood flow when when the heart contracts the high pressure in the aorta propels through the arteries into the coronary veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Define collateral circulation

A

Anastomoses are are where blood from branches of more than one artery that supply the same region connect

They provide alternate routes known as collateral circulation for blood to reach a particular organ or tissue

The myocardium as many anastomoses that provide detours for arterial blood if a main route becomes obstructed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The left and right corral arteries deliver blood to the heart. How do they branch out?

A

Left -> circumflex branch & anterior interventricular branch

Right -> marginal branch & posterior interventricular branch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the 4 principal tributaries caring blood into the coronary sinus?

A

Great cardiac vein
Middle cardiac vein
Small cardiac vein
Anterior cardiac vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe the general histology of cardiac muscle fibers

A
  • They are shorter and less circular than skeletal muscles
  • They have branching which gives a staircase appearance
  • One centrally located nucleus (sometimes 2)
  • Ends of cardiac fibers are connected to one another by thickenings called intercalated discs
  • Have larger and more numerous mitochondria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Describe desmosomes and gap junctions within cardiac muscle fibre

A

Within intercalated discs are desmosomes and gap junctions

Desmosomes hold fibers together and gap junctions allow muscle APs to conduct from one muscle fibre to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Describe autorhymitc fibers and their 2 main functions

A

They repeatedly generate APs that trigger heart contractions and have 2 important functions:

  1. act as a pacemaker - setting the rhythm of electrical excitation that causes contraction
  2. from the cardiac conduction system, a network of specialized cardiac muscle fibers that provide a path for each cycle of cardiac excitation to progress through the heart
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Describe the 5 steps of the cardiac conduciton system

A
  1. Excitation begins in the sinoatrial (SA) node located in the right atrial wall, which repeatedly depolarize to threshold spontaneously, termed the pacemaker potential. When threshold it reached an AP propagates via gap junctions causing the two atria to contract simultaneously
  2. AP reached the atrioventricular (AV) node, located in the interatrial septum, where it slows allowing time for the atria to empty their blood into the ventricles
  3. AP then enters the atrioventricular (AV) bundle - the only place where APs can conduct from atria to ventricles
  4. AP enters right and left bundle branches that extend through the interventricular septum towards apex
  5. Purkinje fibers rapidly conduct the PA at the apex upward to the remainder of the ventricular myocardium, causing ventricular contraction pushing blood toward SV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is an artificial pacemaker useful for?

A

When the SA node becomes damage or diseases an artificial pacemaker can send out small electrical currents to stimulate the heart to contract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the 3 steps of an action potential in a ventricular contractile giber?

A
  1. Depolarization - resting potential is close to -90mV and when it is brought to threshold its fast voltage gated Na+ channels open, causing rapid influx producing a rapid depolarization
  2. Plateau (maintained depolarization) due to Ca2+ inflow when voltage-gated slow Ca2+ channels open and K+ outflow when some K+ channels open
  3. Repolarization due to closure of Ca2+ channels and K+ outflow when additional voltage-raged K+ channels open
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How does the refractory period differ in cardiac muscle compared to skeletal muscle?

A

Another contraction cannot begin until relaxation is well under way thus, tetanus (maintained contraction) cannot occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Describe the 3 following waves in an ECG: P wave, QRS complex, and T wave

A

P wave - small upward deflect on the ECG representing atrial depolarization which spreads from the SA node though contractile fibers in both atria

QRS complex - begins as a downward deflection and then contained as a upright triangular eave and then back down representing rapid ventricular depolarization as the PA spreads through the ventricular contractile fibers

T wave - smaller and wider upward deletion that indicates ventricular depolarization as the ventricles start to relax

  • The ECG is flat during the plateau period of steady depolarization
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the clinical significant of ECG readings?

A

The size of waves can provide clues on abnormalities

Ex. large P wave indicates enlargement of atrium, large Q wave may indicate myocardial infarction, large R wave indicated enlarged ventricles, flat T waves indicates lack of oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How do ECG waves correlate with atrial and ventricular diastole?

A
  1. Depolarization of atrial contractile fibers produces P wave
  2. Atrial systole (contraction)
  3. Depolarization of ventricular contractive fibers produces QRS complex
  4. Ventricular systole (contraction)
  5. Depolarization of ventricular contractive fibers produces T wave
  6. Ventricular diastole (relaxation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Describe the pressure and volume changes during the atrial systole of the cardiac cycle

A
  1. Depolarization of SA node cause atrial depolarization (p wave)
  2. Atrial deporlaization causes atrial systole, forcing blood through the open AV valves into ventricles
  3. Atrial systole contributes 25mL of blood volume in each ventricle, ending with 130mL in each at the end, known as the end-disastolic volume (EDV)
  4. QPR complex marks onset of ventricular depolarization
37
Q

Describe the pressure and volume changes during the ventricular systole of the cardiac cycle

A
  1. Ventricular depolarization causes ventricular systole, pressure rises in ventricles and pushes blood against the AV valves, forcing them shut - ~0.5 seconds SL and AV valves are shut known as isovolumetric contraction - cardiac muscles are contracting but not yet shortening
  2. When left ventricular pressure surpasses aortic pressure (80mmHg) and right ventricular pressure rises above pressure in pulmonary trunk (20mmHg) both SL valves open, known as ventricular ejection
  3. The ventricle ejects blood and the volume remaining in each ventricle at the end of systole, about 60mL, is the end-systolic volume (ESV)
  4. The T wave marks onset of ventricular depolarization
38
Q

What is the stroke volume?

A

The volume ejected per beat from each ventricle equals the end-diastolic volume (EDV) - end systolic volume (ESD)

SV = EDV - ESV

39
Q

Describe the pressure and volume changes during the relaxation period of the cardiac cycle

A
  1. Ventricular depolarization causes ventricular diastole - pressure in chambers fall and blood in aorta and trunk begin to flow backward toward regions of lower pressure in ventricles - as pressure rises all 4 valves close, a period known as isovolumetric relaxation
  2. When ventricular pressure drops below atrial pressure, the AV voles open, and ventricular filling begins
40
Q

There are 4 heart sounds cause by closing of the valves but which 2 are loud enough to be heard?

A

S1 (lubb) - caused by blood turbulence associated with closure of the AV valves soon after ventricular systole begins (louder and longer)

S2 (dupp) - blood turbulence associated with closure of the SL valves at the beginning of ventricular diastole

41
Q

Define heart murmur

A

Abnormal sound consisting of a clicking, rushing, or gurgling noise

They are most frequently discovered in children between the ages of 2 and 4 and they often subside/disappear with growth

In adults, they indicate a valve disorder

42
Q

Define cardiac output

A

the volume of blood ejected from the left (or right) ventricle into the aorta (or pulmonary trunk) each minute

CO = SV x HR

43
Q

Define cardiac reserve

A

the difference between a persons maximum cardiac output and cardiac output at rest

Athletes many have cardiac reserves 7x their resting CO where those with heart disease may have little to no reserve

44
Q

Describe the following 3 factors that regulate stroke volume: preload, contractility, afterload

A

Preload (stretch): a greater preload prior to contraction increases the force of contraction, a relationship known as the frank-starling law of the heart

Contractility: the strength of contraction at any given preload

Afterload: ejection of blood from the heart begins when pressure in the right ventricle exceeds the pressure in the pulmonary trunk and when the pressure in the left ventricle exceeds the pressure in the aorta

45
Q

Preload is proportional to the end-diastolic volume (EDV) - what 2 key factors determine the EDV?

A
  1. The duration of the ventricular diastole
  2. Venous return - the volume of blood returning to the right ventricle

When heart read increases, stroke volume decreases due to the short filling time causing a lower EDV

46
Q

What substances influence contractility?

A

Positive inotropic agents increase contractility and negative inotropic agents decrease it

Positive agents often promote Ca2+ inflow during cardiac potentials which strengthens the force of the next contraction

47
Q

Where is the cardiovascular centre located?

A

Medulla oblongata

48
Q

Describe the autonomic regulation of heart rate

A

Proprioceptors, chemoreceptors (chemical changes in blood), and baroreceptors (stretching of arteries) detect changes in activity and send nerve impulses to the cardiovascular center

The cardiovascular center directs output but increasing or decreasing the frequency of nerve impulses in both the sympathetic and parasympathetic branches of the ANS

Sympathetic: cardiac accelerator nerves extend out to the SA node, AV node, and myocardium - they trigger the release of NE, which binds to mardiac muscle fibers which a) in SA node speeds rate of spontaneous depolarization and b) in contractile fibers in ventricle/atria enhances Ca2+ entry increasing contractility

Parasympathetic: nerves reach heart via left and right vagus (X) nerves which release AcH that decreases HR by slowing the rather of spontaneous depolarization in autorhymic fibers

49
Q

How do hormones and cations influence the heart?

A

Hormones: Epi, NE, and thyroid hormones enhance hearts pumping effectiveness by increasing HR and contractility

Cations: cations are crucial for production of AP in particular, K+, Ca2+, and Na+

  • High K+ decrease HR and contractility as it blocks AP generation
  • High Na+ decrease HR and contractility as it blocks Ca2+ inflow
50
Q

Tachycardia vs bradycardia

A

Tachycardia - elevated resting heart rate that is one sign of hyperthyroidism
Bradycardia - a resting heart rate under 50b/min, typically in athletes

51
Q

Men typically have a higher resting HR than women

True or False

A

False

52
Q

Define arteriosclerosis

A

Thickening of the walls of arteries and loss of elasticity

One form is atherosclerosis, a progressive disease characterized by the formation of walls in the large and medium arteries of lesions called atherosclerotic plaques

53
Q

Define ventricular fibrillation

A

Most deadly arrhythmia, in which contractions of the ventricular fibers are completely asynchronous so that the ventricles quiver rather than contract in a coordinated way

Circulatory failure and death will occur unless there is immediate medical intervention

53
Q

Define ventricular fibrillation

A

Most deadly arrhythmia, in which contractions of the ventricular fibers are completely asynchronous so that the ventricles quiver rather than contract in a coordinated way

Circulatory failure and death will occur unless there is immediate medical intervention

54
Q

Which of the following deflection waves are correctly matched with the following event?

A) P wave/ atrial repolarization
B) T wave/ atrial repolarization
C) P wave/ ventricular depolarization
D) QRS complex/ ventricular depolarization

A

D) QRS complex/ ventricular depolarization

55
Q

During exercise oxygen delivery rises as cardiac output rises because

A) respiration increases
B) skeletal muscle fibers increase in numbers
C) skeletal muscle fibers increase in size
D) skeletal muscle develop more capillary networks

A

D) skeletal muscle develop more capillary networks

56
Q

A patient involved in a car accident has severed the vagus nerve (X). Which of the following symptoms will the patient exhibit?

A) bradycardia
B) increase in heart rate
C) increased strength of contraction
D) decreased preload

A

B) increase in heart rate

57
Q

Which chamber of the heart has the thickest walls?

A) right atrium
B) right ventricle
C) left atrium
D) left ventricle

A

D) left ventricle

58
Q

A patient has pulmonary edema but not peripheral edema. Which of the following is probably true of the patient’s heart?

A) The patient’s left ventricle is failing.
B) The patient’s right ventricle is failing.
C) The patient’s left atrium is failing.
D) The patient’s right atrium is failing.

A

A) The patient’s left ventricle is failing.

59
Q

Closure of the aortic and pulmonary semilunar valves is the onset of

A) ventricular systole
B) depolarization of the SA node
C) atrial systole
D) ventricular diastole

A

D) ventricular diastole

60
Q

End-diastolic volume (EDV) is

A) blood ejected out of the ventricle
B) blood located in the atria at the end of diastole
C) blood ejected from the atria
D) blood in the ventricle at the end of relaxation

A

D) blood in the ventricle at the end of relaxation

61
Q

Cardiac muscle differs from skeletal muscle in that cardiac muscle cells

A) are involuntary
B) are organized in bundles
C) are wrapped in connective tissue sheaths
D) are larger than skeletal muscle cells

A

A) are involuntary

62
Q

An individual appears in the ER with severed chordae tendineae in the right ventricle. The result of this would be

A) decrease blood volume to the pulmonary trunk
B) eversion of the tricuspid valve
C) all of these are results of severed chordae tendineae
D) reduced valve efficiency

A

C) all of these are results of severed chordae tendineae

63
Q

Identify the structure in the adult that represents the remnant of the fetal connection between the pulmonary trunk and the aorta.

A) ligamentum arteriosum
B) foramen ovale
C) ligamentum venosum
D) ductus arteriosus

A

A) ligamentum arteriosum

64
Q

The plateau phase of the cardiac action potential is, in part, due to

voltage-gated potassium channels
voltage-gated fast sodium ion channels
voltage-gated slow calcium channels
ligand-gated channels

A

voltage-gated slow calcium channels

65
Q

A P-Q segment on an electrocardiogram indicates

A) time required for action potential to travel from SA to Purkinje fibers

B) time from ventricle depolarization to ventricular repolarization

C) synchronized contraction of the atria chambers

A

A) time required for action potential to travel from SA to Purkinje fibers

66
Q

Which of the following terms is not associated with cardiac muscle fibers?

mononucleated
striated
intercalated discs
voluntary

A

voluntary

67
Q

An ECG electrocardiogram when compared to a previous test can determine all except

enlarged heart
if regions of the heart are damaged
if the conducting pathway is abnormal
brain waves

A

brain waves

68
Q

Which of the following statements about sinoatrial node (SA) is incorrect?

A) It propagates action potentials that reach the Purkinje cells.
B) It is in the left atrial wall.
C) It can depolarize spontaneously without nervous stimulation.
D) It is the pacemaker of the heart.

A

B) It is in the left atrial wall.

69
Q

Oxygen is presented to the myocardium by

A) blood flow through the heart
B) coronary arteries
C) coronary sinus
D) passing through the fossa ovalis

A

B) coronary arteries

70
Q

The mechanism of closing a semilunar valve is

A) an increase in ventricular pressure
B) a decrease in ventricular pressure
C) an increase in atrial pressure
D) a decrease in atrial pressure

A

B) a decrease in ventricular pressure

71
Q

Atrioventricular valves open

A) the same time semilunar valves open
B) during ventricular systole
C) due to increased tension from chordae tendineae
D) when atrial pressure is greater than ventricular pressure

A

D) when atrial pressure is greater than ventricular pressure

72
Q

Blood flows into coronary vessels

when the heart relaxes
when the pulmonary artery is under pressure
when the heart contracts
when the aorta is under low pressure

A

when the heart relaxes

73
Q

The left side of the heart pumps oxygenated blood to all tissues except

myocardium of the heart
head and upper arms
trunk and lower limbs of the body
pulmonary alveoli of the lungs

A

pulmonary alveoli of the lungs

74
Q

These provide detours for arterial blood if a main route becomes obstructed.

valves
branches
anastomoses
radicals

A

anastomoses

75
Q

Which of the following vessels transport deoxygenated blood into the right atrium?

circumflex branch
marginal branch
right coronary artery
coronary sinus

A

coronary sinus

76
Q

Which of the following structures contain valves that regulate blood flow?

A) the superior and inferior vena cava and the entry into the right atrium
B) between the atrium and ventricle on the left side and the right side
C) the right and left pulmonary veins and entry into the left atrium
D) between the coronary sinus and the right atrium

A

B) between the atrium and ventricle on the left side and the right side

77
Q

The left coronary artery branches into the

posterior interventricular branch
circumflex branch
marginal branch
All of the choices are correct.

A

circumflex branch

78
Q

The exchange of nutrients and gases occurs across the membranes of

arteries
capillaries
veins
arterioles

A

capillaries

79
Q

The coronary sinus returns blood from the myocardium into the

left atrium
right ventricle
right atrium
left ventricle

A

right atrium

80
Q

Which heart valve can be described as containing three flaps with chordae tendineae and allowing deoxygenated to pass through it?

aortic semilunar valve
pulmonary semilunar valve
bicuspid valve
tricuspid valve

A

tricuspid valve

81
Q

Which chambers of the heart contain deoxygenated blood?

left and right ventricular chambers
left atrium and left ventricle
right atrium and right ventricle
left and right atrial chambers

A

right atrium and right ventricle

82
Q

The contraction of the papillary muscles and the attached chordae tendineae function to

eject blood into the greater vessels
close the semilunar valves
prevent the valve cusps from entering into the atrial chambers
opens and stabilizes the atrioventricular valves

A

prevent the valve cusps from entering into the atrial chambers

83
Q

An analysis of the electrocardiogram can reveal all except

stroke volume
an enlarged heart
abnormalities in the conduction pathway
damaged areas in the heart

A

stroke volume

84
Q

When the SA node reaches threshold it triggers an action potential that is spread across the atria.

FALSE
TRUE

A

TRUE

85
Q

An increase in extracellular potassium (hyperkalemia) would result in

increase in stroke volume
decrease in heart rate
decrease in afterload
increase in heart rate

A

decrease in heart rate

86
Q

Atrial repolarization on an electrocardiogram is

masked by the QRS complex
QRS complex
the P wave
T wave

A

masked by the QRS complex

87
Q

A patient is presented in the emergency room complaining of chest pain. The electrocardiogram indicated a myocardial infarction, what was irregular on the ECG?

elevated T wave
enlarged Q wave
wide QRS complex
P wave

A

enlarged Q wave

88
Q

Ventricular repolarization is identified on the ECG by which wave/complex?

T
P-Q
QRS
P

A

T

BIO 235 Final (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions