Biology class 12th solved questions paper:: क्लास 12th क्वेश्चन पेपर सॉल्वड
1. What does operon model represent?
(A) Gene synthesis
(B) Gene expression
(C) Gene regulation
(D) Gene function
Ans:::(C) Gene regulation
2. Thalamus is edible part in which of the following?
(A) Annona
(B) Apple
(C) Orange
(D) All of these
Ans:: (B) Apple
3. DNA is genetic material of?
(A) TMV
(B) Bacteriophage
(C) Both (A) and (B)
(D) None of these
Ans:: (B) Bacteriophage
4. Flow of energy in food chain
of an ecosystem is ?
(A) Unidirectional
(B) Bidirectional
(C) Multidirectional
(D) None of these
Ans:::(A) Unidirectional
5. Which of the following is not a biofertilizer?
(A) Azotobacter
(B) Bacillus thuringiensis
(C) Azolla
(D) Clostridium
Ans:: (B) Bacillus thuringiensis
6.Tuberculosis is transmitted by?
(A) Water
(B) Air
(C) Insect
(D) Contact
Ans:: (B) Air
7. Bio-reactors in optimal conditions produce
(A) Product
(B) Organism
(C) Medium
(D) All of these
Ans:: (A) Product
8. Aril is edible in which of the following fruits?
(A) Myristica
(B) Litchi
(C) Annona
(D) All of these
Ans:: (B) Litchi
9. Indicator of SO₂ pollution is
(A) Algae
(B) Lichen
(C) Fungi
(D) All of these
Ans:: (B) Lichen
10. Honey is made by?
(A) male honeybee
(B) Queen honeybee
(C) Worker honeybee
(D) Both ‘A’ and ‘B
Ans:: (C) Worker honeybee
11. Which disease is found in hen?
(A) Cholera
(B) Smut
(C) Both ‘A’ and ‘B’
(D) Ranikhet
Ans:: (D) Ranikhet
12. The flour of Idli and Dosa is made by the use of which microbe?
(A) Bacteria
(B) Lactobacillus
(C) Virus
(D) Yeast
Ans::: (A) Bacteria
13. Agarose is extracted from?
(A) Maize
(B) Sea weeds
(C) Cycas
(D) None of these
Ans:: (B) Sea weeds
14. Operon model was proposed by?
(A) Watson and Crick
(B) Nirenberg
(C) Jacob and Monad
(D) None of them
Ans:::(C) Jacob and Monad
15. Menstrual cycle occurs in
(A) Human
(B) Monkey
(C) Chimpanzee
(D) All of these
Ans:: (D) All of these
16. Binary fission occurs in
(A) Amoeba
(B) Paramecium
(C) Both ‘A’ and ‘B’
(D) None of these
Ans::(C) Both ‘A’ and ‘B’
17. In a DNA molecule, the cytosine is 18%,percentage of adenine will be ?
(A) 64
(B) 36
(C) 85
(D) 32
Ans::: (D) 32
18. Widal test is done to confirm
(A) Malaria
(B) Typhoid
(C) AIDS
(D) Cancer
Ans:: (B) Typhoid
19. HIV attacks on which of the following cells?
(A) B-cell
(B) T-cell
(C) Epithelial cell
(D) T-helper cell
Ans:::(D) T-helper cell
20. The substances to which an immune response is produced, are called
(A) Allergens
(B) Vaccines
(C) Antibodies
(D) Antigens
Ans:::(D) Antigens
21. Chemical released due to allergy is
(A) Histamine
(B) Serotonin
(C) Both ‘A’ and ‘B’
(D) None of these
Ans:::(C) Both ‘A’ and ‘B’
22. Which one forms endosperm after fusion with male gamete?
(A) Oospores
(B) Antipodals
(C) Synergids
(D) Secondary nucleus
Ans:::(D) Secondary nucleus
23. One gene pair hides the effect of another gene pair. This phenomenon is
(A) Epistasis
(B) Dominance
(C) Mutation
(D) None of these
Ans:::(A) Epistasis
24. A sequence of three bases on rRNA which binds to mRNA codon is
(A) Triplet
(B) Non-sense codon
(C) Anticodon
(D) Termination codon
Ans:: (C) Anticodon
25. The group of Wuchereria bancrofti which causes filaria in human being is ??
(A) Protozoa
(B) Bacteria
(C) Virus
(D) Helminth
Ans:: (D) Helminth
