Complete Body Fluids & Circulation Question Bank & Solutions (50 Questions)
Q1 of 50
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Blood is a type of:
(A)
Epithelial tissue
(B)
Connective tissue
(C)
Muscular tissue
(D)
Nervous tissue
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Correct Answer: (B) Connective tissue
Blood is a fluid connective tissue with plasma as matrix.
Q2 of 50
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Percentage of plasma in blood is about:
(A)
25%
(B)
45%
(C)
55%
(D)
75%
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Correct Answer: (C) 55%
Plasma forms roughly 55% of blood; formed elements ~45%.
Q3 of 50
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The plasma protein responsible for clotting is:
(A)
Albumin
(B)
Globulin
(C)
Fibrinogen
(D)
Haemoglobin
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Correct Answer: (C) Fibrinogen
Fibrinogen is converted to fibrin during clotting.
Q4 of 50
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Serum is plasma without:
(A)
Water
(B)
Clotting factors
(C)
Glucose
(D)
Ions
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Correct Answer: (B) Clotting factors
Serum = plasma minus clotting factors (fibrinogen).
Q5 of 50
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Normal RBC count per mm³ is about:
(A)
5000–8000
(B)
1.5–3.5 lakh
(C)
5–5.5 million
(D)
120
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Correct Answer: (C) 5–5.5 million
RBCs number 5–5.5 million/mm³.
Q6 of 50
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Lifespan of a human RBC is:
(A)
10 days
(B)
120 days
(C)
1 year
(D)
24 hours
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Correct Answer: (B) 120 days
RBCs live about 120 days.
Q7 of 50
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RBCs are destroyed in the:
(A)
Liver
(B)
Spleen
(C)
Kidney
(D)
Heart
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Correct Answer: (B) Spleen
The spleen is the graveyard of RBCs.
Q8 of 50
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Mammalian RBCs are unique in lacking a:
(A)
Membrane
(B)
Nucleus
(C)
Cytoplasm
(D)
Haemoglobin
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Correct Answer: (B) Nucleus
Mature mammalian RBCs are enucleate and biconcave.
Q9 of 50
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The most abundant WBC is the:
(A)
Lymphocyte
(B)
Monocyte
(C)
Neutrophil
(D)
Basophil
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Correct Answer: (C) Neutrophil
Neutrophils form 60–65% of WBCs.
Q10 of 50
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The rarest WBC is the:
(A)
Eosinophil
(B)
Basophil
(C)
Neutrophil
(D)
Monocyte
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Correct Answer: (B) Basophil
Basophils are only 0.5–1% of WBCs.
Q11 of 50
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The largest WBC is the:
(A)
Lymphocyte
(B)
Monocyte
(C)
Neutrophil
(D)
Eosinophil
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Correct Answer: (B) Monocyte
Monocytes are the largest leucocytes.
Q12 of 50
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Which WBCs are agranulocytes?
(A)
Neutrophil & eosinophil
(B)
Lymphocyte & monocyte
(C)
Basophil & eosinophil
(D)
Neutrophil & basophil
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Correct Answer: (B) Lymphocyte & monocyte
Lymphocytes and monocytes lack cytoplasmic granules.
Q13 of 50
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Normal platelet count per mm³ is:
(A)
5 million
(B)
6000–8000
(C)
1.5–3.5 lakh
(D)
120
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Correct Answer: (C) 1.5–3.5 lakh
Platelets number 1.5–3.5 lakh/mm³.
Q14 of 50
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Histamine and heparin are released by:
(A)
Neutrophils
(B)
Basophils
(C)
Monocytes
(D)
RBCs
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Correct Answer: (B) Basophils
Basophils release histamine and heparin.
Q15 of 50
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Blood group AB has antibodies:
(A)
Anti-A only
(B)
Anti-B only
(C)
Both anti-A & anti-B
(D)
None
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Correct Answer: (D) None
AB has both antigens and no antibodies — universal recipient.
Q16 of 50
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The universal donor blood group is:
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Correct Answer: (D) O
O lacks A and B antigens, so it can donate to all.
Q17 of 50
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Antigen present on RBCs of group A is:
(A)
A
(B)
B
(C)
Both
(D)
None
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Correct Answer: (A) A
Group A carries antigen A and anti-B antibody.
Q18 of 50
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Erythroblastosis fetalis arises from incompatibility of:
(A)
ABO
(B)
Rh factor
(C)
MN groups
(D)
HLA
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Correct Answer: (B) Rh factor
It is due to Rh incompatibility between mother and foetus.
Q19 of 50
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The ion essential for blood clotting is:
(A)
Na⁺
(B)
K⁺
(C)
Ca²⁺
(D)
Cl⁻
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Correct Answer: (C) Ca²⁺
Calcium ions are required at several clotting steps.
Q20 of 50
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Fibrinogen is converted into fibrin by:
(A)
Prothrombin
(B)
Thrombin
(C)
Heparin
(D)
Thromboplastin
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Correct Answer: (B) Thrombin
Thrombin acts on fibrinogen to form fibrin.
Q21 of 50
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A natural anticoagulant present in blood is:
(A)
Fibrin
(B)
Thrombin
(C)
Heparin
(D)
Prothrombin
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Correct Answer: (C) Heparin
Heparin prevents intravascular clotting.
Q22 of 50
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Vitamin required for prothrombin synthesis is:
(A)
Vitamin A
(B)
Vitamin C
(C)
Vitamin D
(D)
Vitamin K
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Correct Answer: (D) Vitamin K
Vitamin K is needed for clotting factor synthesis.
Q23 of 50
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Lymph differs from blood in lacking:
(A)
WBCs
(B)
RBCs
(C)
Plasma
(D)
Proteins
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Correct Answer: (B) RBCs
Lymph has no RBCs.
Q24 of 50
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Fats absorbed from the intestine are carried by:
(A)
Blood plasma
(B)
Lymph (lacteals)
(C)
RBCs
(D)
Platelets
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Correct Answer: (B) Lymph (lacteals)
Lacteals of the lymphatic system absorb fats.
Q25 of 50
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Open circulation is found in:
(A)
Annelids
(B)
Vertebrates
(C)
Arthropods
(D)
Fishes
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Correct Answer: (C) Arthropods
Arthropods and molluscs have open circulation.
Q26 of 50
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Single circulation occurs in:
(A)
Fishes
(B)
Birds
(C)
Mammals
(D)
Reptiles
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Correct Answer: (A) Fishes
Fishes have single circulation with a 2-chambered heart.
Q27 of 50
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A complete double circulation is seen in:
(A)
Amphibians
(B)
Reptiles
(C)
Birds and mammals
(D)
Fishes
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Correct Answer: (C) Birds and mammals
Birds and mammals have 4-chambered hearts and complete double circulation.
Q28 of 50
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The human heart has how many chambers?
(A)
Two
(B)
Three
(C)
Four
(D)
Five
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Correct Answer: (C) Four
Two atria and two ventricles.
Q29 of 50
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The thickest chamber wall belongs to the:
(A)
Right atrium
(B)
Left atrium
(C)
Right ventricle
(D)
Left ventricle
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Correct Answer: (D) Left ventricle
The left ventricle pumps blood to the whole body.
Q30 of 50
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The heart is covered by the:
(A)
Peritoneum
(B)
Pericardium
(C)
Pleura
(D)
Meninges
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Correct Answer: (B) Pericardium
A double-walled pericardium with fluid surrounds the heart.
Q31 of 50
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The valve between the right atrium and right ventricle is:
(A)
Bicuspid
(B)
Tricuspid
(C)
Aortic
(D)
Pulmonary
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Correct Answer: (B) Tricuspid
The tricuspid valve has three cusps.
Q32 of 50
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The bicuspid (mitral) valve lies between the:
(A)
Right atrium & ventricle
(B)
Left atrium & ventricle
(C)
Ventricle & aorta
(D)
Atria
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Correct Answer: (B) Left atrium & ventricle
The bicuspid valve guards the left atrioventricular opening.
Q33 of 50
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The pacemaker of the heart is the:
(A)
AV node
(B)
SA node
(C)
Bundle of His
(D)
Purkinje fibres
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Correct Answer: (B) SA node
The SA node initiates each heartbeat.
Q34 of 50
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Correct sequence of impulse conduction is:
(A)
AVN→SAN→His→Purkinje
(B)
SAN→AVN→His→Purkinje
(C)
His→SAN→AVN→Purkinje
(D)
Purkinje→His→AVN→SAN
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Correct Answer: (B) SAN→AVN→His→Purkinje
SA node → AV node → bundle of His → Purkinje fibres.
Q35 of 50
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One cardiac cycle at 72 bpm lasts about:
(A)
0.4 s
(B)
0.8 s
(C)
1.2 s
(D)
2 s
Show Answer & NCERT Explanation
Correct Answer: (B) 0.8 s
At 72 beats/min each cycle is ~0.8 seconds.
Q36 of 50
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The first heart sound "lub" is due to closure of:
(A)
Semilunar valves
(B)
AV valves
(C)
Aorta
(D)
Pulmonary vein
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Correct Answer: (B) AV valves
Lub = atrioventricular valves closing.
Q37 of 50
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Cardiac output of a healthy human is about:
(A)
1 L/min
(B)
5 L/min
(C)
15 L/min
(D)
70 mL/min
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Correct Answer: (B) 5 L/min
≈ stroke volume (70 mL) × heart rate (72) ≈ 5 L/min.
Q38 of 50
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Stroke volume is approximately:
(A)
7 mL
(B)
70 mL
(C)
700 mL
(D)
7 L
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Correct Answer: (B) 70 mL
About 70 mL of blood is ejected per beat.
Q39 of 50
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The QRS complex of an ECG represents:
(A)
Atrial depolarisation
(B)
Ventricular depolarisation
(C)
Ventricular repolarisation
(D)
Atrial repolarisation
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Correct Answer: (B) Ventricular depolarisation
QRS = ventricular depolarisation (contraction).
Q40 of 50
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The T wave of an ECG represents:
(A)
Atrial contraction
(B)
Ventricular contraction
(C)
Ventricular repolarisation
(D)
SA node firing
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Correct Answer: (C) Ventricular repolarisation
The T wave is ventricular repolarisation.
Q41 of 50
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The P wave corresponds to:
(A)
Atrial depolarisation
(B)
Ventricular depolarisation
(C)
Repolarisation
(D)
Heart sound
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Correct Answer: (A) Atrial depolarisation
The P wave marks atrial depolarisation.
Q42 of 50
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The only artery carrying deoxygenated blood is the:
(A)
Aorta
(B)
Pulmonary artery
(C)
Carotid artery
(D)
Renal artery
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Correct Answer: (B) Pulmonary artery
The pulmonary artery takes deoxygenated blood to the lungs.
Q43 of 50
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The only vein carrying oxygenated blood is the:
(A)
Vena cava
(B)
Pulmonary vein
(C)
Hepatic vein
(D)
Renal vein
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Correct Answer: (B) Pulmonary vein
The pulmonary vein returns oxygenated blood to the heart.
Q44 of 50
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Vessels carrying blood away from the heart are:
(A)
Veins
(B)
Arteries
(C)
Capillaries
(D)
Lymphatics
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Correct Answer: (B) Arteries
Arteries carry blood away from the heart.
Q45 of 50
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Valves are present in:
(A)
Arteries
(B)
Veins
(C)
Capillaries
(D)
All vessels
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Correct Answer: (B) Veins
Veins have valves to prevent backflow against gravity.
Q46 of 50
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The cardiac centre is located in the:
(A)
Cerebrum
(B)
Cerebellum
(C)
Medulla oblongata
(D)
Hypothalamus
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Correct Answer: (C) Medulla oblongata
The medulla oblongata houses the cardiac centre.
Q47 of 50
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Heart rate is decreased by the:
(A)
Sympathetic nerves
(B)
Vagus (parasympathetic) nerve
(C)
Adrenaline
(D)
Thyroxine
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Correct Answer: (B) Vagus (parasympathetic) nerve
The parasympathetic vagus nerve slows the heart.
Q48 of 50
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Persistent blood pressure above 140/90 mmHg indicates:
(A)
Anaemia
(B)
Hypertension
(C)
Hypotension
(D)
Leukaemia
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Correct Answer: (B) Hypertension
This defines hypertension (high blood pressure).
Q49 of 50
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Narrowing of coronary arteries by plaque is called:
(A)
Angina
(B)
Atherosclerosis
(C)
Anaemia
(D)
Embolism
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Correct Answer: (B) Atherosclerosis
Atherosclerosis underlies coronary artery disease.
Q50 of 50
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The exchange of materials between blood and tissues occurs across:
(A)
Arteries
(B)
Veins
(C)
Capillaries
(D)
Aorta
Show Answer & NCERT Explanation
Correct Answer: (C) Capillaries
Thin one-cell-thick capillary walls allow exchange.