The Bihar Board Class 12 Biology Exam is a vital paper for students aiming to excel in board exams and competitive tests like NEET. Biology forms the foundation of life sciences, covering both Botany and Zoology. To score high marks, students must focus on objective-type questions as they are concept-based and test-depth understanding.
This article provides 75 important Bihar Board Class 12 Biology Objective Questions with Options and Answers based on the latest syllabus prescribed by the Bihar School Examination Board (BSEB). These questions are highly useful for both board preparation and competitive exam revision.
Bihar Board Class 12 Biology Objective Question 2026 | 75 MCQs with Answers
Bihar Board Class 12 Biology Objective Questions with Options and Answers
1. The powerhouse of the cell is —
(a) Ribosome (b) Mitochondria (c) Nucleus (d) Chloroplast
Answer: Mitochondria
2. The functional unit of life is —
(a) Tissue (b) Organ (c) Cell (d) Organ system
Answer: Cell
3. Photosynthesis occurs in —
(a) Cytoplasm (b) Ribosome (c) Chloroplast (d) Nucleus
Answer: Chloroplast
4. The site of protein synthesis is —
(a) Mitochondria (b) Ribosome (c) Vacuole (d) Nucleus
Answer: Ribosome
5. The process of converting glucose into pyruvate is —
(a) Krebs cycle (b) Glycolysis (c) Photosynthesis (d) Fermentation
Answer: Glycolysis
6. Which is the hereditary material?
(a) RNA (b) DNA (c) Protein (d) Lipid
Answer: DNA
7. The opening and closing of stomata are controlled by —
(a) Guard cells (b) Root hairs (c) Phloem (d) Xylem
Answer: Guard cells
8. The father of genetics is —
(a) Darwin (b) Mendel (c) Morgan (d) Watson
Answer: Gregor Johann Mendel
9. The tissue that transports water in plants is —
(a) Phloem (b) Xylem (c) Parenchyma (d) Collenchyma
Answer: Xylem
10. The smallest unit of heredity is —
(a) Chromosome (b) Gene (c) DNA (d) Nucleus
Answer: Gene
11. Vitamin D is synthesized by —
(a) Skin (b) Kidney (c) Liver (d) Intestine
Answer: Skin
12. The process of energy production in absence of oxygen is —
(a) Photosynthesis (b) Respiration (c) Anaerobic respiration (d) Fermentation
Answer: Anaerobic respiration
13. The blood cells responsible for clotting are —
(a) RBC (b) WBC (c) Platelets (d) Plasma
Answer: Platelets
14. The human heart has —
(a) 2 chambers (b) 3 chambers (c) 4 chambers (d) 5 chambers
Answer: 4 chambers
15. The functional unit of the kidney is —
(a) Neuron (b) Nephron (c) Alveoli (d) Glomerulus
Answer: Nephron
16. The main excretory product in humans is —
(a) Ammonia (b) Uric acid (c) Urea (d) Carbon dioxide
Answer: Urea
17. The brain part that controls posture and balance is —
(a) Cerebrum (b) Cerebellum (c) Medulla (d) Pons
Answer: Cerebellum
18. The process of milk turning into curd is caused by —
(a) Virus (b) Fungi (c) Lactic acid bacteria (d) Protozoa
Answer: Lactic acid bacteria
19. Blood is a —
(a) Tissue (b) Organ (c) Fluid (d) Organ system
Answer: Tissue
20. The hormone regulating blood sugar level is —
(a) Thyroxine (b) Insulin (c) Adrenaline (d) Estrogen
Answer: Insulin
21. The site of photosynthesis in a plant cell is —
(a) Chloroplast (b) Mitochondria (c) Vacuole (d) Golgi body
Answer: Chloroplast
22. The living part of xylem is —
(a) Tracheid (b) Xylem fibre (c) Xylem parenchyma (d) Vessel
Answer: Xylem parenchyma
23. The first step of respiration is —
(a) Krebs cycle (b) Electron transport chain (c) Glycolysis (d) Fermentation
Answer: Glycolysis
24. The structural and functional unit of nervous system is —
(a) Nephron (b) Neuron (c) Axon (d) Synapse
Answer: Neuron
25. The blood group discovered by Landsteiner is —
(a) ABO (b) MN (c) Rh (d) Both a and c
Answer: ABO
26. In plants, the loss of water through stomata is called —
(a) Respiration (b) Transpiration (c) Photosynthesis (d) Diffusion
Answer: Transpiration
27. The process of fusion of gametes is known as —
(a) Fertilization (b) Mitosis (c) Meiosis (d) Budding
Answer: Fertilization
28. The organ that filters blood is —
(a) Heart (b) Liver (c) Kidney (d) Lungs
Answer: Kidney
29. The largest gland in the human body is —
(a) Pancreas (b) Liver (c) Thyroid (d) Pituitary
Answer: Liver
30. The green pigment of plants is —
(a) Chlorophyll (b) Xanthophyll (c) Carotene (d) Anthocyanin
Answer: Chlorophyll
31. The exchange of gases in lungs takes place through —
(a) Alveoli (b) Bronchi (c) Trachea (d) Bronchioles
Answer: Alveoli
32. The process of cell division forming gametes is —
(a) Mitosis (b) Meiosis (c) Binary fission (d) Amitosis
Answer: Meiosis
33. The carrier of oxygen in blood is —
(a) RBC (b) WBC (c) Platelets (d) Plasma
Answer: RBC
34. The human eye image forms on —
(a) Cornea (b) Retina (c) Lens (d) Iris
Answer: Retina
35. The largest organ of the human body is —
(a) Heart (b) Liver (c) Skin (d) Brain
Answer: Skin
36. The process of synthesis of food in plants is —
(a) Respiration (b) Photosynthesis (c) Transpiration (d) Fermentation
Answer: Photosynthesis
37. The mode of nutrition in fungi is —
(a) Parasitic (b) Saprophytic (c) Autotrophic (d) Holozoic
Answer: Saprophytic
38. DNA replication occurs in —
(a) Cytoplasm (b) Nucleus (c) Ribosome (d) Golgi body
Answer: Nucleus
39. The enzyme present in saliva is —
(a) Pepsin (b) Trypsin (c) Amylase (d) Lipase
Answer: Amylase
40. The blood vessels carrying blood away from the heart are —
(a) Veins (b) Arteries (c) Capillaries (d) Venules
Answer: Arteries
41. The process of removal of waste from the body is —
(a) Excretion (b) Respiration (c) Circulation (d) Filtration
Answer: Excretion
42. Which vitamin is essential for blood clotting?
(a) Vitamin A (b) Vitamin B (c) Vitamin K (d) Vitamin C
Answer: Vitamin K
43. The end product of photosynthesis is —
(a) CO₂ (b) Glucose (c) Oxygen (d) Both b and c
Answer: Both b and c
44. Male reproductive organ in flower is —
(a) Stigma (b) Stamen (c) Ovary (d) Sepal
Answer: Stamen
45. The vector of malaria is —
(a) Housefly (b) Anopheles mosquito (c) Culex (d) Sandfly
Answer: Anopheles mosquito
46. The basic unit of classification is —
(a) Species (b) Genus (c) Family (d) Order
Answer: Species
47. The process by which green plants prepare food is —
(a) Photosynthesis (b) Respiration (c) Transpiration (d) Fermentation
Answer: Photosynthesis
48. Which part of brain controls involuntary actions?
(a) Cerebellum (b) Medulla oblongata (c) Cerebrum (d) Hypothalamus
Answer: Medulla oblongata
49. Insulin is secreted by —
(a) Liver (b) Pancreas (c) Kidney (d) Thyroid
Answer: Pancreas
50. The study of heredity is called —
(a) Ecology (b) Genetics (c) Cytology (d) Taxonomy
Answer: Genetics
51. The process of converting nitrogen into usable form by bacteria is called —
(a) Photosynthesis (b) Nitrogen fixation (c) Respiration (d) Fermentation
Answer: Nitrogen fixation
52. Which organelle is called the ‘suicidal bag’ of the cell?
(a) Ribosome (b) Lysosome (c) Mitochondria (d) Golgi body
Answer: Lysosome
53. The largest cell in the human body is —
(a) Nerve cell (b) Egg cell (c) Muscle cell (d) WBC
Answer: Egg cell
54. The number of chromosomes in human body cells is —
(a) 23 (b) 46 (c) 44 (d) 48
Answer: 46
55. The plants which grow in desert conditions are called —
(a) Hydrophytes (b) Mesophytes (c) Xerophytes (d) Epiphytes
Answer: Xerophytes
56. Which of the following diseases is caused by a virus?
(a) Malaria (b) Tuberculosis (c) Influenza (d) Cholera
Answer: Influenza
57. The fluid part of blood is —
(a) Plasma (b) Platelets (c) RBC (d) WBC
Answer: Plasma
58. The main organ for photosynthesis is —
(a) Root (b) Stem (c) Leaf (d) Flower
Answer: Leaf
59. Which gas is released during respiration?
(a) Oxygen (b) Nitrogen (c) Carbon dioxide (d) Hydrogen
Answer: Carbon dioxide
60. The pigment that gives colour to human skin is —
(a) Chlorophyll (b) Melanin (c) Haemoglobin (d) Keratin
Answer: Melanin
61. The plant hormone responsible for cell elongation is —
(a) Auxin (b) Cytokinin (c) Gibberellin (d) Ethylene
Answer: Auxin
62. The non-living part of xylem is —
(a) Xylem vessel (b) Xylem parenchyma (c) Xylem fibre (d) Both a and c
Answer: Both a and c
63. The process of breaking down food in cells to release energy is —
(a) Photosynthesis (b) Respiration (c) Excretion (d) Circulation
Answer: Respiration
64. The largest bone in the human body is —
(a) Humerus (b) Femur (c) Tibia (d) Radius
Answer: Femur
65. The normal temperature of the human body is —
(a) 36°C (b) 37°C (c) 38°C (d) 39°C
Answer: 37°C
66. The smallest bone in the human body is —
(a) Stapes (b) Femur (c) Ulna (d) Fibula
Answer: Stapes
67. The first step in digestion of food is —
(a) In stomach (b) In small intestine (c) In mouth (d) In large intestine
Answer: In mouth
68. Which vitamin is known as ascorbic acid?
(a) Vitamin A (b) Vitamin B (c) Vitamin C (d) Vitamin D
Answer: Vitamin C
69. Which part of the plant absorbs water and minerals?
(a) Root (b) Stem (c) Leaf (d) Flower
Answer: Root
70. The process by which plants lose water in vapour form is —
(a) Transpiration (b) Respiration (c) Photosynthesis (d) Evaporation
Answer: Transpiration
71. The main constituent of plant cell wall is —
(a) Starch (b) Cellulose (c) Protein (d) Lipid
Answer: Cellulose
72. The male gamete in humans is —
(a) Ovum (b) Sperm (c) Zygote (d) Embryo
Answer: Sperm
73. The process of release of ovum from ovary is —
(a) Menstruation (b) Ovulation (c) Fertilization (d) Implantation
Answer: Ovulation
74. The gestation period in humans is about —
(a) 6 months (b) 9 months (c) 10 months (d) 8 months
Answer: 9 months
75. The first scientist to see a living cell under microscope was —
(a) Robert Hooke (b) Leeuwenhoek (c) Watson (d) Mendel
Answer: Anton van Leeuwenhoek
Tips to Score Full Marks in Biology Objective Section
- Study NCERT Line by Line – Most BSEB questions are directly from NCERT.
- Make Flashcards for definitions, scientists’ names, and diagrams.
- Practice Daily MCQs to increase accuracy.
- Revise Formulas and Cycles like Krebs cycle, Photosynthesis, etc.
- Attempt Previous Year Papers to identify repeated questions.
Conclusion-Bihar Board Class 12 Biology Objective Question 2026
Preparing with these 75 Bihar Board Class 12 Biology Objective Questions with Options and Answers will help you master every important concept and perform confidently in the final exam. Focus on understanding concepts rather than memorizing them, and you’ll easily score high in the Biology objective section.
FAQs on Bihar Board Class 12 Biology Objective Question
1. How many objective questions are asked in the Bihar Board Biology Exam?
Usually, 35 to 40 objective questions are asked carrying one mark each.
2. Are the objective questions from NCERT syllabus?
Yes, all questions are based on the NCERT syllabus.
3. How to prepare for Biology objective questions effectively?
Revise NCERT, practice previous year questions, and use flashcards for revision.
4. Is there any negative marking for objective questions in Bihar Board exams?
No, there is no negative marking.
5. Which topics are most important in Biology objective section?
Genetics, Human Physiology, Cell Biology, and Plant Physiology are most important.
6. Is Biology objective section easy to score?
Yes, with proper practice and conceptual clarity, it’s easy to score high.
7. What is the full marks of Biology paper in Class 12 Bihar Board?
The total marks are 100 (Theory – 70, Practical – 30).
8. Are these objective questions useful for NEET too?
Yes, these questions help strengthen NEET basics as well.
9. How can I download Bihar Board Biology question paper?
You can download it from the official BSEB website (biharboardonline.bihar.gov.in).
10. Where can I get more Biology objective questions with answers?
You can visit educational blogs, NCERT exemplars, and BSEB model papers.