Ch.17)Heart Part 2

How many pulmonary veins bring oxygenated blood into the left atrium?

A. 2
B. 3
C. 4
D. 5

C. 4

Pectinate muscles are found in the left atrium:

A. Always
B. Only in the left auricle
C. Only in the right ventricle
D. Never

B. Only in the left auricle

The bicuspid valve is also known as the:

A. Tricuspid valve
B. Pulmonary valve
C. Mitral valve
D. Aortic valve

C. Mitral valve

How many cusps does the bicuspid valve have?

A. 1
B. 2
C. 3
D. 4

B. 2

Why is the left ventricular wall thicker than the right ventricular wall?

A. It contains more valves
B. It pumps blood to the lungs
C. It works harder pumping blood to the entire body
D. It contains the SA node

C. It works harder pumping blood to the entire body

Which valve is located between the left ventricle and the aorta?

A. Tricuspid valve
B. Mitral valve
C. Pulmonary semilunar valve
D. Aortic semilunar valve

D. Aortic semilunar valve

The "Lub" heart sound occurs when:

A. Semilunar valves close
B. Ventricles relax
C. AV valves close
D. Blood enters the atria

C. AV valves close

The "Dub" heart sound occurs when:

A. AV valves close
B. Semilunar valves close
C. Atria contract
D. Blood enters the ventricles

B. Semilunar valves close

A heart murmur suggests:

A. Increased cardiac output
B. Valve dysfunction
C. Normal aging
D. Increased oxygenation

B. Valve dysfunction

At rest, the heart beats approximately:

A. 50 bpm
B. 60 bpm
C. 75 bpm
D. 100 bpm

C. 75 bpm

During passive ventricular filling, approximately what percentage of blood moves from the atria into the ventricles?

A. 20%
B. 30%
C. 50%
D. 70%

D. 70%

The remaining blood enters the ventricles during:

A. Ventricular systole
B. Atrial systole
C. Ventricular diastole
D. Cardiac arrest

B. Atrial systole

Contraction of the heart is called:

A. Diastole
B. Automaticity
C. Systole
D. Repolarization

C. Systole

Relaxation of the heart is called:

A. Diastole
B. Systole
C. Depolarization
D. Auscultation

A. Diastole

Isovolumetric contraction means:

A. Same pressure on both sides of the heart
B. Same volume of blood on both sides of the heart
C. Same oxygen level on both sides
D. Equal wall thickness

B. Same volume of blood on both sides of the heart

Which structure serves as the heart's natural pacemaker?

A. AV node
B. Purkinje fibers
C. SA node
D. Bundle of His

C. SA node

Automaticity of SA nodal cells is primarily due to:

A. Sodium pumps
B. Leak-gated calcium channels
C. Potassium channels only
D. Gap junctions

B. Leak-gated calcium channels

Electrical impulses spread rapidly between cardiac muscle cells through:

A. Desmosomes
B. Gap junctions
C. Chordae tendineae
D. Valves

B. Gap junctions

The AV node delays the electrical impulse primarily to:

A. Increase blood pressure
B. Allow ventricles time to fill with blood
C. Allow atria time to finish contracting
D. Prevent depolarization

C. Allow atria time to finish contracting

The Bundle of His is located:

A. In the aorta
B. At the top of the interventricular septum
C. In the right ventricle only
D. Within the pulmonary trunk

B. At the top of the interventricular septum

Put these structures in the correct conduction order:

A. SA node → AV node → Bundle of His → Bundle branches → Purkinje fibers
B. AV node → SA node → Purkinje fibers → Bundle branches
C. SA node → Purkinje fibers → AV node → Bundle branches
D. SA node → Bundle branches → AV node → Purkinje fibers

A. SA node → AV node → Bundle of His → Bundle branches → Purkinje fibers

Purkinje fibers cause ventricular contraction to spread:

A. From top to bottom
B. From right to left
C. From apex upward
D. Randomly throughout the ventricles

C. From apex upward

The sympathetic nervous system generally:

A. Slows heart rate
B. Increases heart rate and contractility
C. Stops SA node firing
D. Causes bradycardia

B. Increases heart rate and contractility

The parasympathetic nervous system generally:

A. Increases heart rate
B. Causes tachycardia
C. Decreases heart rate and force of contraction
D. Increases stroke volume

C. Decreases heart rate and force of contraction

Which cranial nerve is primarily responsible for parasympathetic slowing of the heart?

A. CN III
B. CN V
C. CN VII
D. CN X

D. CN X

Sinus rhythm is defined as:

A. <60 bpm
B. 60-100 bpm
C. >100 bpm
D. Irregular rhythm

B. 60-100 bpm

Sinus tachycardia is:

A. Less than 60 bpm
B. Greater than 100 bpm
C. Exactly 100 bpm
D. No heartbeat

B. Greater than 100 bpm

Sinus bradycardia is:

A. Below 60 bpm
B. Above 100 bpm
C. Between 60-100 bpm
D. Irregular

A. Below 60 bpm

A well-trained long-distance runner may normally exhibit:

A. Ventricular fibrillation
B. Sinus bradycardia
C. Cardiac arrest
D. Asystole

B. Sinus bradycardia

Pulse is created by:

A. Expansion and recoil of arteries following ventricular contraction
B. Atrial depolarization
C. Valve closure only
D. Coronary blood flow

A. Expansion and recoil of arteries following ventricular contraction

On an EKG, the P wave represents:

A. Ventricular depolarization
B. Ventricular repolarization
C. Atrial depolarization
D. Atrial repolarization

C. Atrial depolarization

The QRS complex represents:

A. Atrial depolarization
B. Ventricular depolarization
C. Ventricular repolarization
D. Cardiac arrest

B. Ventricular depolarization

The T wave represents:

A. Atrial depolarization
B. Ventricular depolarization
C. Ventricular repolarization
D. AV nodal delay

C. Ventricular repolarization

Why is the QRS complex larger than the P wave?

A. Ventricles contain more muscle cells than atria
B. Atria conduct electricity faster
C. Ventricles depolarize slower
D. The AV node amplifies signals

A. Ventricles contain more muscle cells than atria

A flat-line EKG indicates:

A. Fibrillation
B. Tachycardia
C. Bradycardia
D. Asystole

D. Asystole

Ventricular fibrillation is dangerous because:

A. Atria stop working
B. Ventricles cannot effectively pump blood to the body
C. Coronary vessels enlarge
D. Blood becomes oxygen-rich

B. Ventricles cannot effectively pump blood to the body

A patient has a heart rate of 140 bpm while sprinting. According to these notes, this is most likely:

A. Sinus tachycardia
B. Ventricular fibrillation
C. Cardiac arrest
D. Asystole

A. Sinus tachycardia

A patient develops a clot that completely blocks coronary blood flow to part of the myocardium. What is the most likely outcome?

A. Endocarditis
B. Pericarditis
C. Myocardial infarction
D. Bradycardia only

C. Myocardial infarction

Why can myocardial infarction alter the EKG waveform?

A. Dead cardiac cells cannot properly conduct electrical signals
B. The SA node becomes larger
C. The ventricles disappear
D. The valves stop existing

A. Dead cardiac cells cannot properly conduct electrical signals

A person collapses and has ventricular fibrillation. What treatment is specifically used to reset the heart's electrical activity?

A. Auscultation
B. Defibrillation
C. Angiography
D. Diastole

B. Defibrillation

During cardiac arrest, CPR is performed primarily to:

A. Close valves
B. Generate EKG waves
C. Maintain blood flow to vital organs until advanced treatment is available
D. Stop electrical impulses

C. Maintain blood flow to vital organs until advanced treatment is available

A patient has damage to the AV node. Which conduction step would be directly impaired?

A. Initiation of the heartbeat
B. Delay between atrial and ventricular contraction
C. Ventricular repolarization
D. Coronary circulation

B. Delay between atrial and ventricular contraction

If the sympathetic nervous system becomes highly active during an emergency, which change would occur?

A. Decreased heart rate
B. Decreased contractility
C. Increased heart rate and force of contraction
D. Asystole

C. Increased heart rate and force of contraction

A depolarization wave moving toward a positive electrode will appear as:

A. Negative deflection
B. Positive deflection
C. No deflection
D. Flatline

B. Positive deflection

Which rhythm is considered normal despite being below 60 bpm?

A. Ventricular fibrillation
B. Sinus bradycardia
C. Asystole
D. Cardiac arrest

B. Sinus bradycardia

Why is atrial fibrillation usually less immediately dangerous than ventricular fibrillation?

A. Atria are larger than ventricles
B. Gravity still helps move blood from atria to ventricles
C. Coronary arteries compensate
D. The AV node stops working

B. Gravity still helps move blood from atria to ventricles

If the SA node stops generating impulses entirely, which major function is lost first?

A. Coronary circulation
B. Normal rhythm initiation
C. Valve closure
D. Blood oxygenation

B. Normal rhythm initiation

__________ is an abnormal, rapid heart rhythm often over 100 bpm.

Bradycardia

Tachycardia

Sinus Rhythm

Tachycardia

The P wave on an EKG represents ventricular depolarization.

True

False

False

The parasympathetic nervous system increases heart rate.

True

False

False

Myogenic activity allows the heart to beat even when removed from the body (temporarily).

True

False

True

Which of the following best describes systole?

Relaxation and filling of chambers

Opening of AV valves

Contraction and ejection of blood

Closure of the semilunar valves

Contraction and ejection of blood

The “dub” sound is caused by the opening of the semilunar valves.

True

False

False

70% of blood coming into the atria passes passively into the ventricles due to a pressure difference.

Atrial Diastole

The leftover 30% of blood is ejected into the ventricles, followed by the closing of the AV valves.

Atrial Systole

Increased pressure in the ventricles causes the opening of the semilunar valves.

Ventricular systole

Passive filling of the ventricles since they are empty from ejecting into the semilunar valves.

Ventricular Diastole

Which of the following is NOT part of the conduction system of the heart?

A. AV node

B. Bundle of his

C. SA node

D. AV valve

D. AV valve

During atrial systole,

A. the semilunar valves are open

B. the atrioventricular valves are open

C. atrial blood passes passively into the ventricles

D. the ventricles are in systole

B. the atrioventricular valves are open

Normal heart sounds are caused by which of the following events?

A. excitation of the SA node

B. closure of the heart valves

C. friction of blood against the chamber walls

D. contraction of ventricular muscle

B. closure of the heart valves

Blood is pushed out from the right atrium into the right ventricle (every last drop of it) by this muscle. Can you name the structure?

A. papillary muscle

B. chordae tendineae

C. pectinate muscle

D. AV valves

C. pectinate muscle

The “lubb” sound heard with a stethoscope is caused by:

A. blood rushing through the semilunar valves when they open

B. turbulence in the blood when the AV valves open

C. contraction of the atria

D. turbulence in the blood when the semilunar valves close

B. turbulence in the blood when the AV valves open

Step 1 of Conduction System

70% of the blood coming into the atria passively flows into the ventricles, followed by the closing of the AV valves

Step 2 of Conduction System

SA node generates action potential and depolarizes in a wave-like motion toward the left atria and the AV node

Step 3 of Conduction System

Atrial systole causes the leftover 30% of blood to be ejected into the ventrices

Step 4 of Conduction System

The AV node receives the electrical impulse but delays further depolarization to allow the atria to contract

Step 5 of Conduction System

Electrical impulse reaches common Bundle of His

Step 6 of Conduction System

Impulse is sent down the right and left bundle braches

Step 7 of Conduction System

Impulse travels along Purkinje fibers

Step 8 of Conduction System

Cardiomyocytes depolarize in a wave-like motion through the ventricles, causing the ventricles to contract bottom up

Step 9 of Conduction System

Blood is ejected into semilunar valves