HorthooZ – Kerala GK, PSC Questions & Onam Quiz

Q1 Multiple Choice Question

In humans, blood passes twice through the heart to complete one complete circulatory round. This phenomenon is called:

A Incomplete circulation B Open circulation C Double circulation D Single circulation

Q2 Multiple Choice Question

The volume of blood contained in each ventricle at the end of ventricular diastole (filling phase) just prior to contraction is known as:

A End-Systolic Volume (ESV, ~50 mL) B Tidal Volume (~500 mL) C Stroke Volume (SV, ~70 mL) D End-Diastolic Volume (EDV, ~120 mL)

Q3 Multiple Choice Question

Which laboratory diagnostic test measures the rate at which red blood cells settle down in a vertical anticoagulated tube, serving as a non-specific marker of bodily inflammation?

A Clotting Time (CT) B Bleeding Time (BT) C Total WBC Count (TC) D Erythrocyte Sedimentation Rate (ESR)

Q4 Multiple Choice Question

The 'Bainbridge reflex' (atrial reflex) produces an involuntary increase in heart rate primarily in response to:

A Excessive accumulation of carbon dioxide in the aortic arch B Increased venous return stretching the mechanoreceptors in the right atrial wall C Direct thermal stimulation of the hypothalamus D A sharp drop in systemic arterial blood pressure at the carotid sinus

Q5 Multiple Choice Question

Which granulocytic white blood cells secrete histamine, serotonin, and heparin, participating in inflammatory reactions?

A Basophils B Neutrophils C Lymphocytes D Erythrocytes

Q6 Multiple Choice Question

Which intrinsic hemodynamic principle states that within physiological limits, the stroke volume of the heart increases in direct response to an increase in the end-diastolic volume (preload)?

A Frank-Starling Law of the Heart B Poiseuille's Law C Bohr Effect D Haldane Effect

Q7 Multiple Choice Question

The narrowing and clogging of arterial lumens due to the deposition of cholesterol, calcium, and fibrous tissue is specifically called:

A Rheumatic heart disease B Atherosclerosis C Arteriosclerosis alone D Varicose veins

Q8 Multiple Choice Question

Which natural anticoagulant produced primarily by liver and mast cells prevents intravascular blood clotting inside healthy blood vessels?

A Hirudin B Hemoglobin C Fibrinogen D Heparin

Q9 Multiple Choice Question

Which of the following describes the unique architectural feature that defines a 'portal circulatory system'?

A A system of valves directly joining an artery directly to an adjacent lymph node B A blood vessel carrying oxygenated blood under extremely high hydrostatic pressure C A vascular system that begins in capillaries and ends in another capillary bed before reaching the heart D A collateral circuit bypassing the central capillary bed through direct arteriovenous anastomoses

Q10 Multiple Choice Question

Which specialized conducting tissue located in the lower corner of the right atrium is known as the 'Pacesetter' of the human heart?

A Sino-atrial (SA) node B Atrio-ventricular (AV) node C Bundle of His D Purkinje fibers

Q11 Multiple Choice Question

Cardiac output is defined as the volume of blood pumped out by each ventricle per minute. How is it calculated, and what is its standard resting value in a healthy adult?

A Cardiac Output = End-Diastolic Volume - End-Systolic Volume (~70 mL/min) B Cardiac Output = Stroke Volume ÷ Heart Rate (~0.8 Litres/min) C Cardiac Output = Stroke Volume × Heart Rate (~5 Litres/min) D Cardiac Output = Blood Pressure × Peripheral Resistance (~120 Litres/min)

Q12 Multiple Choice Question

Which portal circulatory system is well-developed in fishes and amphibians, reduced in reptiles and birds, but completely absent in adult human mammals?

A Hepatic portal system B Hypophyseal portal system C Renal portal system D Coronary circuit

Q13 Multiple Choice Question

Which is the largest type of White Blood Cell (Leukocyte) found in human peripheral blood?

A Basophil B Lymphocyte C Monocyte D Neutrophil

Q14 Multiple Choice Question

Sickle cell anemia is caused by a point mutation in the beta-globin gene resulting in the substitution of which amino acid?

A Glutamic acid substituted for Valine B Valine substituted for Glutamic acid C Alanine substituted for Proline D Lysine substituted for Glycine

Q15 Multiple Choice Question

The fraction of total blood volume occupied by packed red blood cells following centrifugation is clinically defined as the:

A Hematocrit / Packed Cell Volume (PCV) B Erythrocyte Sedimentation Rate (ESR) C Blood viscosity index D Mean Corpuscular Volume (MCV)

Q16 Multiple Choice Question

Pernicious anemia occurs due to impaired erythrocyte maturation resulting from the deficiency of which vitamin or gastric factor?

A Vitamin A (Retinol) B Vitamin D (Calciferol) C Vitamin B12 (Cyanocobalamin) D Vitamin C (Ascorbic acid)

Q17 Multiple Choice Question

Which artery in the human body is an exception that carries deoxygenated blood instead of oxygenated blood?

A Pulmonary artery B Carotid artery C Aorta D Coronary artery

Q18 Multiple Choice Question

Excessive consumption of nitrate-contaminated drinking water in human infants causes 'Blue Baby Syndrome' (cyanosis) due to the formation of:

A Oxyhemoglobin B Bilirubin C Carboxyhemoglobin D Methemoglobin

Q19 Multiple Choice Question

The process by which motile white blood cells (particularly neutrophils and monocytes) squeeze through narrow pores in intact capillary walls into infected tissues is called:

A Phagocytosis B Agglutination C Hemolysis D Diapedesis

Q20 Multiple Choice Question

In a normal electrocardiogram (ECG) recording, which wave represents the repolarization (relaxation) of the ventricles?

A PR segment B QRS complex C T wave D P wave

Circulatory System