Biology

Cardiovascular and Nervous System

981 Questions

Review the human cardiovascular system through these competitive exam practice questions. Key areas include heart valves, cardiac impulse pathways, and blood pressure regulation. A solid grasp of these fundamentals is crucial for science sections.

Heart anatomy and valvesCardiac impulse conductionBlood pressure mechanicsHeartbeat regulation

Cardiovascular and Nervous System Questions

Multiple choice

The T-wave represents, which of the following events?

  1. Return of the ventricles from an excited to a normal state.

  2. Depolarisation of the atria.

  3. Depolarisation of the ventricles.

  4. Ventricular contraction.

  5. Excitation of the atria.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The T-wave represents the return of the ventricles from an excited to a normal state (repolarisation). The end of the T-wave marks the end of systole.

Multiple choice

Which of the following statements is true regarding the cardiovascular system in a developing fetus?

  1. Blood pressure = stroke volume X heart rate

  2. Left-to-right shunting across the duct is normal in the fetus.

  3. The fetal heart does not start pumping blood until the completion of first trimester.

  4. In a developing fetus, the contractility of the heart is independent of preload and afterload.

  5. The ductus arteriosus can be kept open by the use of certain medicines including indomethacing.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Unlike stroke volume, contractility is independent of preload and afterload and is an innate property of myofibrils. It can be influenced by inotropes (e.g. dobutamine).

Multiple choice

Which of the following separates the right auricle from the right ventricle?

  1. Tricuspid valve

  2. Bicuspid valve

  3. Pericardium

  4. Myocardium

  5. Pericardial fluid
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The tricuspid valve or right atrioventricular valve is present on the right dorsal side of the mammalian heart in between the right atrium and the right ventricle. The function of the valve is to ensure that blood flows from the right atrium to the right ventricle by closing an prevented back flow during ventricle systole.

Multiple choice

ECG records

  1. rate of heart beat

  2. volume of blood pumped

  3. heart diseases

  4. potential difference of cardiac muscle
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

ECG (Electrocardiogram) records the electrical activity of the heart over time, specifically the potential difference (voltage changes) of the cardiac muscle. This is detected through electrodes placed on the skin. It does not directly record rate, volume, or diseases.

Multiple choice

ECG is a method to detect

  1. heart attack

  2. heartblock

  3. coronary thrombosis

  4. all of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

ECG is used to detect various cardiac conditions including heart attacks (myocardial infarction), heart blocks (conduction abnormalities), and coronary thrombosis (clot in coronary arteries). All of these conditions produce characteristic changes in the ECG pattern.

Multiple choice

The place where the heart is situated in humans is

  1. pleural cavity

  2. coelom

  3. mediastinum

  4. both (2) and (3)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The mediastinum is the central compartment of the thoracic cavity. It contains all organs of the thoracic cavity, except the lungs.

Multiple choice

Pulse pressure is ______.

  1. systolic pressure

  2. diastolic pressure

  3. systolic pressure and diastolic pressure

  4. the difference between systolic pressure and diastolic pressure
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Pulse pressure is the arithmetic difference between systolic pressure (peak pressure during heart contraction) and diastolic pressure (minimum pressure between beats). Normal pulse pressure is typically 30-50 mmHg. It reflects the force generated by the heart and arterial elasticity. Options A, B, and C describe individual components but not the definition of pulse pressure itself.

Multiple choice

Purkinje fibres are present ______.

  1. in ventricles

  2. in auricles

  3. in striated muscle fibres

  4. throughout the heart
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Purkinje fibres are specialized cardiac muscle fibers located in the ventricles that form the terminal part of the conduction system. They rapidly transmit electrical impulses from the AV bundle to the ventricular myocardium, ensuring coordinated ventricular contraction.

Multiple choice

Heart beat is initiated in man by __________.

  1. SA node

  2. Purkinje fibres

  3. AV node-adrenaline

  4. Bundle of HIS
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The SA node (sinoatrial node) is the heart's natural pacemaker, located in the right atrium. It spontaneously generates electrical impulses that initiate each heartbeat. These impulses then spread to the AV node, Bundle of His, and Purkinje fibres to coordinate the cardiac cycle.