Formed Elements & Blood Groups — NEET Biology MCQs with Solutions
Free NEET Biology Formed Elements & Blood Groups MCQs with step-by-step solutions (73 questions). Part of Body Fluids and Circulation. Practise online on Prepizo — no login needed.
▶ Practise Formed Elements & Blood Groups online (free)
Questions with solutions
Q1 — Formed Elements & Blood Groups · easy · theory
The most abundant blood cells, which carry oxygen and lack a nucleus in humans, are the:
A. Erythrocytes (RBCs) ✓ Correct
B. Leucocytes (WBCs)
C. Thrombocytes (platelets)
D. Lymphocytes
Solution: RBCs (~5 million/mm³) are enucleate, biconcave and packed with haemoglobin for O₂ transport.
Q2 — Formed Elements & Blood Groups · easy · theory
A person with blood group AB is called a universal ______ because:
A. Recipient; RBCs have no antigens
B. Donor; RBCs have no antigens
C. Recipient; plasma has no anti-A or anti-B antibodies ✓ Correct
D. Donor; plasma has both antibodies
Solution: AB individuals lack anti-A/anti-B antibodies, so can receive any ABO type — universal recipients.
Q3 — Formed Elements & Blood Groups · medium · theory
The granulocyte most abundant among WBCs, phagocytic and the first to reach infection sites, is the:
A. Basophil
B. Eosinophil
C. Lymphocyte
D. Neutrophil ✓ Correct
Solution: Neutrophils (~60–65% of WBCs) are phagocytic and combat infection; lymphocytes handle immunity.
Q4 — Formed Elements & Blood Groups · medium · theory
A person with blood group O is the universal donor because their RBCs:
A. Have Rh antigen only
B. Have no antibodies
C. Have both A and B antigens
D. Have neither A nor B antigens ✓ Correct
Solution: O-group RBCs carry no A/B surface antigens, so they can be given to any ABO recipient.
Q5 — Formed Elements & Blood Groups · hard · theory
Erythroblastosis foetalis occurs when:
A. An Rh⁻ mother carries an Rh⁺ foetus and her anti-Rh antibodies attack the foetal RBCs ✓ Correct
B. Both parents are Rh⁻
C. An Rh⁺ mother carries an Rh⁻ foetus
D. The foetus is blood group O
Solution: In a second Rh⁺ pregnancy, maternal anti-Rh antibodies cross the placenta and destroy foetal RBCs.
Q6 — Formed Elements & Blood Groups · hard · theory
The formed elements of blood are produced (haematopoiesis) mainly in the ______ in adults:
A. Red bone marrow ✓ Correct
B. Spleen only
C. Liver
D. Thymus only
Solution: In adults, red bone marrow is the main site of blood cell formation.
Q7 — Formed Elements & Blood Groups · easy · numerical
An anucleate formed element that survives about 120 days and is destroyed mainly in the spleen and liver is the:
A. Neutrophil
B. Lymphocyte
C. Platelet
D. Erythrocyte (RBC) ✓ Correct
Solution: Mature mammalian RBCs lack a nucleus, live roughly 120 days, and are broken down in the spleen and liver. Platelets live only ~5–9 days and WBCs are nucleated.
Q8 — Formed Elements & Blood Groups · easy · numerical
Which grouping of leucocytes into granulocytes and agranulocytes is entirely correct?
A. Granulocytes: lymphocytes, monocytes; Agranulocytes: neutrophils, basophils, eosinophils
B. Granulocytes: neutrophils, eosinophils, basophils; Agranulocytes: lymphocytes, monocytes ✓ Correct
C. Granulocytes: monocytes, basophils; Agranulocytes: neutrophils, lymphocytes
D. Granulocytes: neutrophils, lymphocytes; Agranulocytes: eosinophils, monocytes
Solution: Neutrophils, eosinophils, and basophils have cytoplasmic granules (granulocytes); lymphocytes and monocytes lack prominent granules (agranulocytes).
Q9 — Formed Elements & Blood Groups · easy · numerical
A person with blood group O who is Rh negative can safely DONATE packed red cells to which of the following in an emergency?
A. Any Rh positive person but no Rh negative person
B. A recipient of any ABO group who is Rh negative ✓ Correct
C. Only AB positive individuals
D. Only other O negative individuals under all circumstances
Solution: O negative red cells carry neither A, B, nor Rh(D) antigens, so they can be given to recipients of any ABO group provided they are also Rh negative (or, for RBCs, to Rh positive recipients too). Restricting to only O negative is unnecessary for the cells.
Q10 — Formed Elements & Blood Groups · easy · numerical
Normal counts in adult human blood are approximately:
A. RBC 8000/mm³, WBC 3.5 lakh/mm³, platelets 5 million/mm³
B. RBC 1.5–3.5 lakh/mm³, WBC 5 million/mm³, platelets 8000/mm³
C. RBC 6000–8000/mm³, WBC 5–5.5 million/mm³, platelets 120/mm³
D. RBC 5–5.5 million/mm³, WBC 6000–8000/mm³, platelets 1.5–3.5 lakh/mm³ ✓ Correct
Solution: Standard NCERT values are ~5–5.5 million RBC/mm³, 6000–8000 WBC/mm³, and 1.5–3.5 lakh platelets/mm³.
Q11 — Formed Elements & Blood Groups · medium · numerical
A woman is Rh negative and her foetus is Rh positive. Erythroblastosis foetalis is more likely in a SUBSEQUENT pregnancy because:
A. Rh positive foetal cells lack all surface antigens and are rejected
B. The first foetus transfers Rh antibodies to the mother permanently
C. The mother produces Rh antigen that attacks her own red cells
D. Maternal anti-Rh antibodies formed after the first exposure cross the placenta and haemolyse foetal RBCs ✓ Correct
Solution: The first Rh-positive pregnancy sensitises the mother to Rh antigen; in a later pregnancy her anti-Rh antibodies cross the placenta and destroy the foetal RBCs, causing erythroblastosis foetalis.
Q12 — Formed Elements & Blood Groups · medium · numerical
Consider the statements about blood coagulation: (i) Calcium ions are essential for several steps of the cascade. (ii) Thrombin converts fibrinogen into fibrin. (iii) Platelets release factors that initiate clotting at the injury site. Which are correct?
A. Only i is correct
B. Only ii and iii are correct
C. Only i and ii are correct
D. i, ii, and iii are all correct ✓ Correct
Solution: All three are correct: Ca²⁺ is needed at multiple cascade steps, thrombin catalyses fibrinogen→fibrin, and injured platelets release thromboplastin-type factors that trigger the cascade.
Q13 — Formed Elements & Blood Groups · medium · numerical
Match the cell with its principal function and choose the correct set: (i) Eosinophil (ii) Basophil (iii) Neutrophil — (p) most abundant phagocyte, first responder to infection (q) resists infections and is associated with allergic responses (r) secretes histamine, serotonin, and heparin.
A. i-q, ii-p, iii-r
B. i-p, ii-q, iii-r
C. i-r, ii-p, iii-q
D. i-q, ii-r, iii-p ✓ Correct
Solution: Eosinophils resist infections and act in allergic reactions, basophils secrete histamine/serotonin/heparin, and neutrophils are the most abundant phagocytic first responders.
Q14 — Formed Elements & Blood Groups · medium · numerical
For a successful ABO transfusion the donor RBC antigens must not meet matching recipient plasma antibodies. Why can an AB-group recipient accept A, B, AB, and O red cells?
A. They produce Rh antibodies that neutralise all ABO antigens
B. Their plasma contains neither anti-A nor anti-B antibodies ✓ Correct
C. Their red cells carry no antigens at all
D. Their plasma contains both anti-A and anti-B antibodies
Solution: Group AB plasma lacks both anti-A and anti-B antibodies, so donor A or B antigens are not agglutinated — making AB the universal recipient (for ABO).
Q15 — Formed Elements & Blood Groups · medium · numerical
Assertion (A): Platelets are cell fragments, not whole cells. Reason (R): They are pinched off from megakaryocytes in the red bone marrow. Choose the correct option.
A. Both A and R are true and R is the correct explanation of A ✓ Correct
B. Both A and R are true but R is not the correct explanation of A
C. A is false but R is true
D. A is true but R is false
Solution: Platelets (thrombocytes) are membrane-bound fragments produced by fragmentation of megakaryocytes in the bone marrow — so R correctly explains why they are fragments rather than whole cells.
Q16 — Formed Elements & Blood Groups · medium · numerical
A student claims: "In adult humans all formed elements are produced in the liver." The correct statement is that in adults these cells are formed mainly in the:
A. Red bone marrow, with lymphocytes also maturing in lymphoid tissues ✓ Correct
B. Thymus alone for all blood cell types
C. Yolk sac throughout life
D. Liver and spleen only, as during the foetal stage
Solution: In adults haematopoiesis occurs chiefly in the red bone marrow; lymphocytes complete maturation in lymphoid organs. Liver/spleen are foetal sites, not the main adult source.
Q17 — Formed Elements & Blood Groups · medium
Match the following leucocytes in Column I with their functions in Column II:
Column I: I. Basophils, II. Neutrophils, III. Monocytes, IV. Eosinophils, V. Lymphocytes
Column II: A. Phagocytes, B. Secrete histamine, serotonin, heparin and involved in inflammatory response, C. Resist infections and are also involved in allergic reaction, D. Immunity, E. Phagocytes
A. I - B, II and III - C, IV - A, V - D
B. I - D, II and III - C, IV - A, V - B
C. I - C, II and III - A, IV - B, V - D
D. I - B, II and III - A, IV - C, V - D ✓ Correct
Solution: Basophils secrete histamine, serotonin and heparin (inflammatory); neutrophils and monocytes are phagocytes; eosinophils resist infection and are involved in allergic reactions; lymphocytes are responsible for immunity.
Q18 — Formed Elements & Blood Groups · easy
Megakaryocytes produce
A. Lymphocytes
B. Blood platelets (thrombocytes) ✓ Correct
C. Bone cells
D. Leucocytes
Solution: Blood platelets (thrombocytes) are cell fragments produced by megakaryocytes, special cells of the bone marrow.
Q19 — Formed Elements & Blood Groups · easy
Which of the following is cell fragments?
A. RBCs
B. Leucocytes
C. Blood platelets ✓ Correct
D. None
Solution: Blood platelets (thrombocytes) are cell fragments produced from megakaryocytes.
Q20 — Formed Elements & Blood Groups · easy
1 mm3 blood has how many blood platelets?
A. 150000 - 350000 ✓ Correct
B. 1.5 million to 3.5 million
C. 10 to 15 lacs
D. 1500-3000
Solution: Platelets are produced at a rate of 1,50,000 to 3,50,000 per mm3 (cubic millimetre) of blood.
Q21 — Formed Elements & Blood Groups · medium
During blood clotting, platelets release
A. Prothrombin
B. Thrombokinase and other blood clotting factor ✓ Correct
C. Thrombin
D. Fibrinogen
Solution: Platelets can release a variety of substances (thrombokinase and other clotting factors) most of which are involved in the coagulation or clotting of blood.
Q22 — Formed Elements & Blood Groups · medium
Find the correct descending order of percentage proportion of leucocytes in human blood.
A. Neutrophils > Basophils > Lymphocytes > Eosinophils > Monocytes
B. Neutrophils > Lymphocytes > Monocytes > Eosinophils > Basophils ✓ Correct
C. Neutrophils > Monocytes > Lymphocytes > Eosinophils > Basophils
D. Neutrophils > Eosinophils > Basophils > Lymphocytes > Monocytes
Solution: By percentage, neutrophils (60-65%) > lymphocytes (20-25%) > monocytes (6-8%) > eosinophils (2-3%) > basophils (0.5-1%).
Q23 — Formed Elements & Blood Groups · medium
Assertion – A physician might order a white cell count for a patient with symptoms of an infection.
Reason – An increase in the number of white blood cells (leukocytes) may indicate that the person is combating an infection.
A. Assertion is true but reason is false.
B. Both assertion and reason are true and reason is correct explanation of assertion. ✓ Correct
C. Both assertion and reason are false.
D. Both assertion and reason are true but reason is not correct explanation of assertion.
Solution: WBCs defend the body against infection, so their count rises when combating an infection; hence a physician orders a WBC count, and the reason correctly explains the assertion.
Q24 — Formed Elements & Blood Groups · easy
Formed elements of blood include –
A. RBC, WBC and blood platelets ✓ Correct
B. All minerals (elements)
C. Proteins present in blood
D. All solutes present in blood
Solution: The formed elements of blood are erythrocytes (RBC), leucocytes (WBC) and platelets, together constituting nearly 45% of the blood.
Q25 — Formed Elements & Blood Groups · easy
Which of the following statements is false?
A. RBCs are formed in the red bone marrow in the adults.
B. RBCs are enucleate in most of the mammals.
C. Erythrocytes/RBC are the least abundant of all the cells in blood. ✓ Correct
D. The number of RBCs in adult man per mm3 of blood is 5 million to 5.5 million.
Solution: RBCs are the most abundant cells of the blood (5-5.5 million per mm3), not the least abundant, so statement 1 is false.
Q26 — Formed Elements & Blood Groups · easy
Life span of human RBC is
A. 120 days ✓ Correct
B. 120 month
C. 120 hours
D. 102 days
Solution: Red blood cells have an average life span of about 120 days, after which they are destroyed in the spleen.
Q27 — Formed Elements & Blood Groups · easy
What is the amount of haemoglobin present in 100 ml of human blood?
A. 45g
B. 10-12g
C. 12-16g ✓ Correct
D. 18-20g
Solution: A healthy individual has 12-16 grams of haemoglobin in every 100 ml of blood.
Q28 — Formed Elements & Blood Groups · easy
Mammalian RBCs are in shape-
A. biconcave ✓ Correct
B. Biconvex
C. Oval
D. Sickle-like
Solution: RBCs are typically biconcave in shape in mammals and lack a nucleus in most.
Q29 — Formed Elements & Blood Groups · medium
All of the following statement are correct about WBCs except –
A. They are nucleate and least constancy in shape
B. They are lesser in number (6000 – 8000 per mm3 blood)
C. They help in blood clotting ✓ Correct
D. They are generally short-lived
Solution: WBCs are nucleated, fewer in number (6000-8000 per mm3) and short-lived; they do not help in blood clotting, that is the role of platelets.
Q30 — Formed Elements & Blood Groups · easy
All of the following are granulocytes, except-
A. Basophils only
B. Lymphocytes and monocytes ✓ Correct
C. Neutrophils
D. Eosinophils
Solution: Neutrophils, eosinophils and basophils are granulocytes; lymphocytes and monocytes are agranulocytes.