Structure & function of heart and blood vessels | Staff Nurse | Mock Test

Structure & function of heart and blood vessels

The heart is a muscular, four-chambered organ that functions as the central pump of the circulatory system, propelling blood throughout the body. It consists of two atria (upper chambers) and two ventricles (lower chambers), working in a coordinated manner to circulate oxygen-rich and oxygen-poor blood. The blood vessels include arteries, which carry blood away from the heart; veins, which return blood to the heart; and capillaries, where the exchange of gases, nutrients, and waste occurs. Together, the heart and blood vessels maintain vital functions such as oxygen delivery, nutrient transport, and removal of metabolic waste, ensuring the body's tissues remain healthy and functional.

Time: 15:00

Which layer of the heart wall is composed of cardiac muscle and is responsible for the heart's pumping action?

[a] Endocardium

[b] Pericardium

[c] Myocardium

[d] Epicardium

Which chamber of the heart receives deoxygenated blood from the superior and inferior vena cava?

[a] Left Ventricle

[b] Left Atrium

[c] Right Ventricle

[d] Right Atrium

The sinoatrial (SA) node, the natural pacemaker of the heart, is located in the wall of which chamber?

[a] Right Atrium

[b] Left Atrium

[c] Right Ventricle

[d] Left Ventricle

On an electrocardiogram (ECG), the P wave represents:

[a] Ventricular depolarization

[b] Atrial depolarization

[c] Ventricular repolarization

[d] The delay at the AV node

The first heart sound (S1 or "lub") is caused by the closure of which valves?

[a] Aortic and Pulmonary valves

[b] Aortic and Mitral valves

[c] Mitral and Tricuspid valves

[d] Pulmonary and Tricuspid valves

Which blood vessels are the primary sites of exchange for gases, nutrients, and waste products between the blood and tissue cells?

[a] Arterioles

[b] Venules

[c] Capillaries

[d] Arteries

The term 'afterload' refers to the:

[a] Volume of blood in the ventricle at the end of diastole.

[b] Intrinsic strength of the myocardial contraction.

[c] Amount of blood ejected with each beat.

[d] Resistance the left ventricle must overcome to eject blood.

What is the primary function of the valves found in veins, particularly in the lower extremities?

[a] To regulate blood pressure

[b] To prevent the backflow of blood

[c] To facilitate nutrient exchange

[d] To increase the oxygen content of blood

Cardiac output is the product of which two factors?

[a] Preload and Afterload

[b] Stroke Volume and Blood Pressure

[c] Heart Rate and Stroke Volume

[d] Contractility and Heart Rate

Which chamber of the heart has the thickest myocardial wall?

[a] Left Ventricle

[b] Right Ventricle

[c] Left Atrium

[d] Right Atrium

The mitral valve prevents blood from flowing back into the:

[a] Right Atrium

[b] Left Atrium

[c] Aorta

[d] Pulmonary Artery

Which of the following vessels carries oxygenated blood?

[a] Superior Vena Cava

[b] Pulmonary Artery

[c] Coronary Sinus

[d] Pulmonary Vein

The brief delay of the electrical impulse at the atrioventricular (AV) node is crucial because it:

[a] Allows the SA node to recharge.

[b] Prevents atrial fibrillation.

[c] Allows the atria to fully contract and empty into the ventricles.

[d] Ensures both ventricles contract simultaneously.

A patient with chronic, untreated hypertension is at high risk for developing:

[a] Right Ventricular Atrophy

[b] Tricuspid Valve Stenosis

[c] Left Ventricular Hypertrophy

[d] A decreased afterload

Which structural characteristic of arteries is most responsible for maintaining blood pressure and flow during diastole?

[a] Their large lumen size

[b] Their elastic recoil properties

[c] The presence of valves

[d] The thinness of their walls

Preload is most directly influenced by:

[a] Systemic vascular resistance

[b] The force of myocardial contraction

[c] Venous return to the heart

[d] Heart rate

A diuretic, such as furosemide, primarily reduces a patient's blood pressure by:

[a] Decreasing preload

[b] Increasing contractility

[c] Increasing afterload

[d] Directly slowing the heart rate

The term for inflammation of the inner lining of the heart, which can damage heart valves, is:

[a] Pericarditis

[b] Myocarditis

[c] Endocarditis

[d] Cardiomyopathy

The "skeletal muscle pump" is an important mechanism for:

[a] Regulating blood flow to the brain

[b] Assisting venous return from the limbs

[c] Increasing arterial pressure

[d] Distributing blood through capillaries

On an ECG, the QRS complex represents the electrical activity associated with:

[a] Atrial contraction

[b] Atrial relaxation

[c] Ventricular contraction (depolarization)

[d] Ventricular relaxation (repolarization)

Which of the following is a direct consequence of a failing right ventricle (right-sided heart failure)?

[a] Pulmonary edema and crackles in the lungs

[b] Decreased pressure in the pulmonary artery

[c] Increased systemic venous pressure and peripheral edema

[d] A bounding arterial pulse

Atherosclerosis is a disease process characterized by plaque buildup primarily within the:

[a] Tunica intima of arteries

[b] Tunica media of veins

[c] Capillary beds

[d] Heart valves

Which part of the cardiac conduction system is responsible for spreading the impulse throughout the ventricular myocardium to ensure a coordinated contraction?

[a] The SA node

[b] The AV node

[c] The chordae tendineae

[d] The Purkinje fibers

The blood vessels that supply the myocardium itself with oxygenated blood are the:

[a] Carotid arteries

[b] Pulmonary arteries

[c] Coronary arteries

[d] Bronchial arteries

An ECG characteristic that would be suggestive of atrial fibrillation is:

[a] Pathologic Q waves

[b] No discernible P waves

[c] Abnormal and bizarre QRS

[d] Elevated ST segment