Preparing for the Bihar Board Intermediate Exam becomes easier when students practice objective questions regularly. This set of Bihar Board Class 12th Biology 75 Objective Questions covers all the important chapters like Reproduction, Genetics, Evolution, Ecology, Biotechnology, and Human Physiology.
Each question is provided with four options and the correct answer, following the latest BSEB exam pattern. This will help students quickly revise and score high in the Biology objective section.
Bihar Board Class 12th Biology 75 Objective Question with Answers | Important MCQs 2025
Biology 75 Objective Question with Answers
1. Which of the following is the site of fertilization in humans?
a) Ovary
b) Uterus
c) Fallopian tube
d) Cervix
Answer: c) Fallopian tube
2. The process of formation of sperm is known as—
a) Oogenesis
b) Spermatogenesis
c) Fertilization
d) Implantation
Answer: b) Spermatogenesis
3. Asexual reproduction occurs through—
a) Fragmentation
b) Gamete formation
c) Conjugation
d) Fusion
Answer: a) Fragmentation
4. Which hormone triggers ovulation?
a) FSH
b) LH
c) Estrogen
d) Progesterone
Answer: b) LH
5. The functional unit of a kidney is—
a) Neuron
b) Nephron
c) Axon
d) Glomerulus
Answer: b) Nephron
6. Mendel is known as the father of—
a) Biology
b) Genetics
c) Evolution
d) Zoology
Answer: b) Genetics
7. Which of the following is a sex-linked disorder?
a) Hemophilia
b) Diabetes
c) Malaria
d) Cancer
Answer: a) Hemophilia
8. The genotype of a pure tall pea plant is—
a) tt
b) TT
c) Tt
d) TTT
Answer: b) TT
9. The chemical nature of a gene is—
a) RNA
b) Protein
c) DNA
d) Lipid
Answer: c) DNA
10. Which of these is an example of homologous organs?
a) Wing of bird and bat
b) Wing of bird and insect
c) Fin of fish and wing of butterfly
d) Eyes of octopus and mammals
Answer: a) Wing of bird and bat
11. Natural selection was proposed by—
a) Lamarck
b) Darwin
c) Morgan
d) Wallace
Answer: b) Darwin
12. Which of the following is used in DNA fingerprinting?
a) RNA polymerase
b) Gel electrophoresis
c) Ribosome
d) Protein ligase
Answer: b) Gel electrophoresis
13. Bt-cotton is resistant to—
a) Virus
b) Bacteria
c) Fungi
d) Insects
Answer: d) Insects
14. Which bacteria convert milk into curd?
a) Lactobacillus
b) Rhizobium
c) Salmonella
d) Vibrio
Answer: a) Lactobacillus
15. The process of making an exact copy of DNA is—
a) Translation
b) Transcription
c) Replication
d) Mutation
Answer: c) Replication
16. Which organ secretes bile?
a) Liver
b) Stomach
c) Pancreas
d) Small intestine
Answer: a) Liver
17. Basic unit of the ecosystem is—
a) Population
b) Community
c) Species
d) Organism
Answer: d) Organism
18. Greenhouse gas is—
a) CO₂
b) N₂
c) O₂
d) H₂
Answer: a) CO₂
19. The term biodiversity was given by—
a) Wilson
b) Darwin
c) Mendel
d) Hackel
Answer: a) Wilson
20. PCR technique is used to—
a) Break DNA
b) Amplify DNA
c) Destroy DNA
d) Repair DNA
Answer: b) Amplify DNA
21. Coral reefs are mostly found in—
a) Cold seas
b) Tropical seas
c) Rivers
d) Lakes
Answer: b) Tropical seas
22. Which vitamin is synthesized in skin by sunlight?
a) Vitamin A
b) Vitamin D
c) Vitamin E
d) Vitamin K
Answer: b) Vitamin D
23. Somatic cells contain—
a) Haploid set
b) Diploid set
c) Triploid set
d) Polyploidy
Answer: b) Diploid set
24. A test-tube baby is developed by—
a) IVF
b) IUD
c) ZIFT
d) AI
Answer: a) IVF
25. AIDS is caused by—
a) HIV
b) Hepatitis virus
c) Plasmodium
d) Mycobacterium
Answer: a) HIV
26. The smallest unit of evolution is—
a) Individual
b) Population
c) Species
d) Community
Answer: b) Population
27. Nitrogen fixation in root nodules is done by—
a) Azotobacter
b) Rhizobium
c) Cyanobacteria
d) Penicillium
Answer: b) Rhizobium
28. Basic unit of life is—
a) Tissue
b) Organ
c) Cell
d) System
Answer: c) Cell
29. Energy currency of cell is—
a) ADP
b) ATP
c) DNA
d) RNA
Answer: b) ATP
30. Powerhouse of the cell is—
a) Chloroplast
b) Ribosome
c) Mitochondria
d) Nucleus
Answer: c) Mitochondria
31. Crossing over occurs in—
a) Mitosis
b) Meiosis-I
c) Meiosis-II
d) Cytokinesis
Answer: b) Meiosis-I
32. Photosynthesis pigment is—
a) Chlorophyll
b) Hemoglobin
c) Keratin
d) Melanin
Answer: a) Chlorophyll
33. Cell division for growth is—
a) Meiosis
b) Mitosis
c) Fission
d) Budding
Answer: b) Mitosis
34. Sickle cell anemia is caused due to—
a) Chromosomal mutation
b) Point mutation
c) Gene deletion
d) Trisomy
Answer: b) Point mutation
35. Vector of malaria is—
a) Culex
b) Female Anopheles
c) Aedes
d) Musca
Answer: b) Female Anopheles
36. Largest gland is—
a) Liver
b) Pancreas
c) Thyroid
d) Salivary gland
Answer: a) Liver
37. Milk teeth are—
a) Temporary teeth
b) Permanent teeth
c) Molars
d) Premolars
Answer: a) Temporary teeth
38. Fossil fuel is—
a) Water
b) Coal
c) Oxygen
d) Nitrogen
Answer: b) Coal
39. DNA discovered by—
a) Franklin
b) Watson
c) Miescher
d) Crick
Answer: c) Miescher
40. Universal donor blood group is—
a) A
b) B
c) O
d) AB
Answer: c) O
41. Insulin is secreted by—
a) Liver
b) Pancreas
c) Kidney
d) Thyroid
Answer: b) Pancreas
42. Pollination by wind is—
a) Hydrophily
b) Zoophily
c) Anemophily
d) Entomophily
Answer: c) Anemophily
43. Smallest bone is—
a) Femur
b) Tibia
c) Stapes
d) Humerus
Answer: c) Stapes
44. Biodegradable pollutant is—
a) DDT
b) Plastic
c) Paper
d) Glass
Answer: c) Paper
45. Father of taxonomy is—
a) Aristotle
b) Linnaeus
c) Darwin
d) Lamarck
Answer: b) Linnaeus
46. Rabies is caused by—
a) Bacteria
b) Virus
c) Fungi
d) Protozoa
Answer: b) Virus
47. Gene bank stores—
a) Seeds
b) Blood
c) Fossils
d) DNA only
Answer: a) Seeds
48. STD is—
a) TB
b) AIDS
c) Typhoid
d) Cholera
Answer: b) AIDS
49. Purest water is—
a) Distilled water
b) Rain water
c) Sea water
d) Well water
Answer: a) Distilled water
50. DNA is made of—
a) Amino acids
b) Nucleotides
c) Lipids
d) Proteins
Answer: b) Nucleotides
51. Air pollution is mainly caused by—
a) CO
b) O₂
c) N₂
d) H₂
Answer: a) CO
52. Human body contains chromosomes—
a) 23
b) 46
c) 44
d) 48
Answer: b) 46
53. Balance is controlled by—
a) Cerebrum
b) Cerebellum
c) Medulla
d) Pons
Answer: b) Cerebellum
54. TB affects—
a) Kidney
b) Heart
c) Lungs
d) Liver
Answer: c) Lungs
55. Vitamin C is—
a) Retinol
b) Riboflavin
c) Ascorbic acid
d) Calciferol
Answer: c) Ascorbic acid
56. Transpiration occurs through—
a) Stomata
b) Lenticels
c) Cuticle
d) All of these
Answer: d) All of these
57. Growth hormone in plants is—
a) ABA
b) Auxin
c) Ethylene
d) Cytokinin
Answer: b) Auxin
58. Hydra reproduces by—
a) Budding
b) Fission
c) Fragmentation
d) Regeneration
Answer: a) Budding
59. Stomata are found in—
a) Root
b) Stem
c) Leaf
d) Flower
Answer: c) Leaf
60. Gas released in photosynthesis is—
a) CO₂
b) O₂
c) N₂
d) H₂
Answer: b) O₂
61. Human heart has—
a) Two chambers
b) Three chambers
c) Four chambers
d) Five chambers
Answer: c) Four chambers
62. Blood is—
a) Tissue
b) Organ
c) Cell
d) Fluid only
Answer: a) Tissue
63. Unit of heredity is—
a) DNA
b) Gene
c) Protein
d) Chromosome
Answer: b) Gene
64. Plasmodium causes—
a) TB
b) Malaria
c) Dengue
d) Cholera
Answer: b) Malaria
65. Renewable resource is—
a) Oil
b) Coal
c) Forest
d) Natural gas
Answer: c) Forest
66. Penicillin discovered by—
a) Fleming
b) Pasteur
c) Jenner
d) Koch
Answer: a) Fleming
67. Amoeba respires through—
a) Gills
b) Skin
c) Body surface
d) Lungs
Answer: c) Body surface
68. Water is carried in plants by—
a) Phloem
b) Xylem
c) Cortex
d) Cambium
Answer: b) Xylem
69. RBC contains—
a) DNA
b) Mitochondria
c) Hemoglobin
d) Nucleus
Answer: c) Hemoglobin
70. Viral disease is—
a) Cholera
b) Polio
c) TB
d) Typhoid
Answer: b) Polio
71. Normal body temperature is—
a) 98.4°F
b) 94°F
c) 80°F
d) 100°F
Answer: a) 98.4°F
72. Photosynthesis occurs in—
a) Mitochondria
b) Chloroplast
c) Nucleus
d) Ribosome
Answer: b) Chloroplast
73. Human right lung has—
a) One lobe
b) Two lobes
c) Three lobes
d) Four lobes
Answer: c) Three lobes
74. Study of fungi is—
a) Botany
b) Mycology
c) Zoology
d) Ecology
Answer: b) Mycology
75. Structural unit of protein is—
a) Glucose
b) Amino acid
c) Fatty acid
d) Nucleotide
Answer: b) Amino acid
FAQs-Biology 75 Objective Question with Answers
1: How many objective questions come in Bihar Board Class 12 Biology exam?
In the Bihar Board Class 12 Biology exam, around 35 objective questions are asked, covering both short and long chapters. Practicing 75 questions improves accuracy.
2: Are these 75 objective questions enough for scoring good marks?
Yes, these 75 curated MCQs cover important topics and help you strengthen your preparation. However, revision of NCERT is also essential.
3: Are the questions based on the latest Bihar Board syllabus?
Yes, all the questions provided here are aligned with the latest Bihar Board Class 12 Biology syllabus and previous year trends.
4: How to prepare Class 12 Biology for full marks?
Focus on NCERT, diagrams, definitions, and daily MCQ practice. Also revise important chapters like Genetics, Evolution, Human Physiology, and Reproduction.
5: Where can I get more Bihar Board objective question sets?
You can request more sets here anytime—Physics, Chemistry, Biology, or any subject series.