1. The oxygen dissociation curve of hemoglobin is –
(A) Linear
(B) Sigmoid
(C) Exponential
(D) Hyperbolic
2. Night blindness is caused due to deficiency of –
(A) Vitamin A
(B) Vitamin C
(C) Vitamin D
(D) Vitamin K
3. Which is the pacemaker of the human heart?
(A) AV Node
(B) SA Node
(C) Bundle of His
(D) Purkinje Fibers
4. The universal energy currency of the cell is –
(A) ATP
(B) ADP
(C) AMP
(D) GTP
5. The functional unit of kidney is –
(A) Nephron
(B) Glomerulus
(C) Loop of Henle
(D) Bowman’s Capsule
6. Which enzyme is called ‘suicidal bag of cell’?
(A) Ribosome
(B) Lysosome
(C) Mitochondria
(D) Golgi body
7. In meiosis, crossing over occurs at –
(A) Leptotene
(B) Pachytene
(C) Zygotene
(D) Diplotene
8. In C4 plants, first stable product of photosynthesis is –
(A) 3-PGA
(B) Oxaloacetate
(C) Malate
(D) PEP
9. In which plant tissue sieve tube is found?
(A) Xylem
(B) Phloem
(C) Collenchyma
(D) Parenchyma
10. Which is a nitrogen-fixing cyanobacterium?
(A) Gelidium
(B) Laminaria
(C) Nostoc
(D) Fucus
11. Which of the following produces erythropoietin hormone?
(A) Kidney
(B) Pancreas
(C) Liver
(D) Heart
12. Genetic material in retrovirus is –
(A) dsDNA
(B) ssRNA
(C) dsRNA
(D) ssDNA
13. Sickle-cell anemia is caused by –
(A) Substitution mutation in β-globin gene
(B) Deletion mutation in α-globin gene
(C) Trisomy of chromosome 21
(D) X-linked recessive mutation
14. Antibody is chemically –
(A) Protein
(B) Lipid
(C) Carbohydrate
(D) Steroid
15. Which vitamin is essential for blood clotting?
(A) Vitamin A
(B) Vitamin B12
(C) Vitamin K
(D) Vitamin E
16. The concept of operon model was proposed by –
(A) Jacob and Monod
(B) Watson and Crick
(C) Beadle and Tatum
(D) Hershey and Chase
17. Which bacteria is used in production of insulin by rDNA technology?
(A) Bacillus subtilis
(B) Rhizobium
(C) Escherichia coli
(D) Agrobacterium
18. Okazaki fragments are found in –
(A) Leading strand
(B) Lagging strand
(C) Both strands
(D) RNA
19. In which part of chloroplast does light reaction take place?
(A) Stroma
(B) Thylakoid membrane
(C) Matrix
(D) Grana
20. The polymerase used in PCR is –
(A) Taq polymerase
(B) DNA polymerase I
(C) RNA polymerase
(D) Reverse transcriptase
21. The process of removal of introns and joining of exons is called –
(A) Replication
(B) Splicing
(C) Transduction
(D) Translation
22. Which hormone is secreted by pancreas?
(A) Insulin
(B) Thyroxine
(C) Cortisol
(D) Adrenaline
23. Which gas is released during photorespiration?
(A) O₂
(B) CO₂
(C) CH₄
(D) H₂
24. Haemophilia is –
(A) Autosomal recessive
(B) Autosomal dominant
(C) X-linked recessive
(D) Y-linked
25. Which blood group is called universal donor?
(A) A
(B) AB
(C) O
(D) B
26. The main function of lymph is –
(A) Transport of hormones
(B) Transport of fat
(C) Oxygen transport
(D) Excretion
27. In humans, fertilization normally occurs in –
(A) Ovary
(B) Uterus
(C) Fallopian tube
(D) Vagina
28. Mycorrhiza is an example of –
(A) Symbiosis
(B) Parasitism
(C) Commensalism
(D) Competition
29. Which is the smallest WBC?
(A) Monocyte
(B) Neutrophil
(C) Basophil
(D) Lymphocyte
30. The enzyme which joins Okazaki fragments is –
(A) Ligase
(B) Helicase
(C) Primase
(D) Polymerase
31. Which plant hormone is responsible for cell elongation?
(A) Cytokinin
(B) Auxin
(C) Gibberellin
(D) Abscisic acid
32. Which pigment absorbs maximum red light during photosynthesis?
(A) Chlorophyll a
(B) Chlorophyll b
(C) Xanthophyll
(D) Carotene
33. Which of the following has a double circulatory system?
(A) Fish
(B) Amphibians
(C) Reptiles
(D) Mammals
34. The energy yield of one molecule of glucose in aerobic respiration is approximately –
(A) 2 ATP
(B) 36 ATP
(C) 38 ATP
(D) 24 ATP
35. In Mendel’s dihybrid cross, phenotypic ratio is –
(A) 3:1
(B) 9:3:3:1
(C) 1:2:1
(D) 2:1
36. Barr body is found in –
(A) Male somatic cell
(B) Female somatic cell
(C) Male germ cell
(D) Y chromosome
37. A codon consists of –
(A) 2 nucleotides
(B) 3 nucleotides
(C) 4 nucleotides
(D) 5 nucleotides
38. Which of the following is a purine base?
(A) Adenine
(B) Cytosine
(C) Thymine
(D) Uracil
39. Which kingdom does Nostoc belong to?
(A) Plantae
(B) Protista
(C) Monera
(D) Fungi
40. The main role of RuBisCO enzyme is –
(A) Glycolysis
(B) Carbon fixation
(C) Photorespiration
(D) Nitrogen fixation
41. Which structure is responsible for protein synthesis?
(A) Lysosome
(B) Ribosome
(C) Golgi body
(D) Peroxisome
42. Antigen-antibody reaction is studied under –
(A) Immunology
(B) Virology
(C) Pathology
(D) Cytology
43. Which hormone regulates sodium reabsorption in kidney?
(A) Insulin
(B) ADH
(C) Aldosterone
(D) Glucagon
44. Who is regarded as the ‘Father of Genetics’?
(A) Darwin
(B) Mendel
(C) Morgan
(D) Linnaeus
45. Which blood vessel carries oxygenated blood from lungs to heart?
(A) Pulmonary artery
(B) Pulmonary vein
(C) Aorta
(D) Coronary artery
46. Which organelle contains its own DNA and ribosomes?
(A) ER
(B) Mitochondria
(C) Golgi complex
(D) Lysosome
47. The deficiency of iodine causes –
(A) Rickets
(B) Goitre
(C) Scurvy
(D) Night blindness
48. Which of the following is a biodegradable pollutant?
(A) Plastic
(B) DDT
(C) Sewage
(D) Mercury
49. In lac operon, the structural genes are –
(A) lac Z, lac Y, lac A
(B) lac I, lac O, lac P
(C) lac A, lac O, lac Z
(D) lac P, lac Z, lac I
50. Which virus causes AIDS?
(A) Influenza virus
(B) HIV
(C) Herpes virus
(D) Adenovirus
51. The common name of Bryophytes is –
(A) Amphibians of plant kingdom
(B) Seedless vascular plants
(C) Flowerless plants
(D) Gymnosperms
52. Which vitamin deficiency leads to rickets?
(A) Vitamin A
(B) Vitamin D
(C) Vitamin E
(D) Vitamin C
53. Which process maintains constancy of chromosome number from generation to generation?
(A) Mitosis
(B) Meiosis
(C) Fertilization
(D) Replication
54. Which enzyme converts pepsinogen to pepsin?
(A) Pepsin
(B) Trypsin
(C) HCl
(D) Rennin
55. Which one is a C₃ plant?
(A) Sugarcane
(B) Maize
(C) Rice
(D) Sorghum
56. The term ‘ecology’ was coined by –
(A) Linnaeus
(B) Haeckel
(C) Darwin
(D) Wallace
57. Which part of brain controls respiration?
(A) Cerebrum
(B) Cerebellum
(C) Medulla oblongata
(D) Hypothalamus
58. Which of the following is an example of ex-situ conservation?
(A) Biosphere reserve
(B) National park
(C) Botanical garden
(D) Wildlife sanctuary
59. Which technique is used for separation of DNA fragments?
(A) Centrifugation
(B) Gel electrophoresis
(C) Chromatography
(D) Spectrophotometry
60. Which is the connecting link between annelida and arthropoda?
(A) Limulus
(B) Peripatus
(C) Balanoglossus
(D) Nereis
Answer Key with Explanation
1. (B) Sigmoid – Hemoglobin-এর oxygen dissociation curve sigmoid হয় cooperative binding এর কারণে।
2. (A) Vitamin A – Vitamin A এর অভাবে rod cell ঠিকমতো কাজ করে না → night blindness।
3. (B) SA Node – SA Node হৃদপিণ্ডের প্রাকৃতিক pacemaker।
4. (A) ATP – Universal energy currency হল ATP।
5. (A) Nephron – Kidney-এর functional unit হল nephron।
6. (B) Lysosome – Lysosome নিজের এনজাইমে কোষ ভেঙে দেয় → “suicidal bag”।
7. (B) Pachytene – Meiosis-I এ pachytene পর্যায়ে crossing over হয়।
8. (B) Oxaloacetate – C₄ উদ্ভিদে প্রথম product = oxaloacetate।
9. (B) Phloem – Sieve tube phloem-এর অংশ।
10. (C) Nostoc – Nostoc হল nitrogen-fixing cyanobacteria।
11. (A) Kidney – Kidney erythropoietin hormone উৎপন্ন করে।
12. (B) ssRNA – Retrovirus-এর genetic material single-stranded RNA।
13. (A) Substitution mutation in β-globin gene – এক অ্যামিনো অ্যাসিড বদলালে sickle cell anemia হয়।
14. (A) Protein – Antibody হল glycoprotein।
15. (C) Vitamin K – Blood clotting-এর জন্য Vitamin K দরকার।
16. (A) Jacob and Monod – Operon model তাঁরা প্রস্তাব করেন (lac operon)।
17. (C) E. coli – Recombinant DNA technology-তে insulin উৎপাদনে ব্যবহৃত হয়।
18. (B) Lagging strand – Okazaki fragment কেবল lagging strand-এ হয়।
19. (B) Thylakoid membrane – Light reaction thylakoid membrane-এ হয়।
20. (A) Taq polymerase – PCR এ Taq polymerase ব্যবহৃত হয় (heat stable)।
21. (B) Splicing – Introns কেটে exons জোড়া দেওয়াকে splicing বলে।
22. (A) Insulin – Pancreas insulin ক্ষরণ করে।
23. (B) CO₂ – Photorespiration-এ CO₂ মুক্তি হয়।
24. (C) X-linked recessive – Haemophilia X-linked recessive রোগ।
25. (C) O – O blood group universal donor।
26. (B) Transport of fat – Lymph মূলত fats পরিবহন করে।
27. (C) Fallopian tube – Fertilization সাধারণত fallopian tube-এ হয়।
28. (A) Symbiosis – Mycorrhiza হল ফাঙ্গাস ও উদ্ভিদের মূলের symbiosis।
29. (D) Lymphocyte – Smallest WBC হলো lymphocyte।
30. (A) Ligase – DNA ligase Okazaki fragments জোড়ে দেয়।
31. (B) Auxin – Auxin cell elongation ঘটায়।
32. (A) Chlorophyll a – প্রধানত লাল আলো শোষণ করে।
33. (D) Mammals – Mammals-এ double circulation সম্পূর্ণ।
34. (C) 38 ATP – Aerobic respiration থেকে ~38 ATP।
35. (B) 9:3:3:1 – Dihybrid cross-এর phenotypic ratio।
36. (B) Female somatic cell – Barr body inactive X chromosome।
37. (B) 3 nucleotides – Codon = 3 nucleotides।
38. (A) Adenine – Adenine ও Guanine = purine bases।
39. (C) Monera – Nostoc prokaryote, Monera kingdom।
40. (B) Carbon fixation – RuBisCO Calvin cycle-এ CO₂ fix করে।
41. (B) Ribosome – Protein synthesis হয় ribosome-এ।
42. (A) Immunology – Antigen-antibody reaction studied under immunology।
43. (C) Aldosterone – Na⁺ reabsorption নিয়ন্ত্রণ করে।
44. (B) Mendel – Genetics-এর জনক Mendel।
45. (B) Pulmonary vein – Lungs থেকে heart-এ O₂ rich blood আনে।
46. (B) Mitochondria – নিজস্ব DNA ও ribosome থাকে।
47. (B) Goitre – Iodine deficiency → goitre।
48. (C) Sewage – Biodegradable pollutant।
49. (A) lac Z, lac Y, lac A – Structural genes of lac operon।
50. (B) HIV – AIDS-এর জন্য দায়ী virus = HIV।
51. (A) Amphibians of plant kingdom – Bryophytes terrestrial + aquatic উভয় বৈশিষ্ট্য রাখে।
52. (B) Vitamin D – Vitamin D deficiency → rickets।
53. (C) Fertilization – Chromosome সংখ্যা প্রজন্মে স্থায়ী রাখে।
54. (C) HCl – Pepsinogen → pepsin HCl দ্বারা সক্রিয় হয়।
55. (C) Rice – Rice হল C₃ plant।
56. (B) Haeckel – Ecology শব্দটি দিয়েছিলেন।
57. (C) Medulla oblongata – Respiration control করে।
58. (C) Botanical garden – Ex-situ conservation উদাহরণ।
59. (B) Gel electrophoresis – DNA fragment separation-এর জন্য ব্যবহৃত।
60. (B) Peripatus – Annelida ও Arthropoda-র connecting link।