CBSE Class 12 Biotechnology Sample Paper 2023

SECTION A

1. Male sterility is widely used in crops such as maize, sunflower for hybridproduc tion. Male sterile plants are created by introducing a gene encoding-
(a) Barnase protein
(b) TA29
(c) Barstar protein
(d) Coat protein

Answer : A

2. Body builders prefer to drink buffalo milk to build muscle mass. Determine the reason for this?
(a) Easier to digest
(b) Lower fat content
(c) Higher calcium and phosphorus content
(d) Balanced calorie source

Answer : C

3. An industrially important secondary metabolite which is used as a red pigment in
lipstics and dye for silk is obtained from-
(a) Datura stramonium
(b) Lithospermum erythrorhizon
(c) Digitalis lanata
(d) Coptis japonica

Answer : B

4. Proteome of a given cell is dynamic because :
(a) In response to Internal and external changes the biochemical machinery of the cell could be changed.
(b) In response to Internal and external changes the biochemical machinery of the cell could not be changed.
(c) No direct relationship exists between Internal and external changes in the biochemical machinery of the cell.
(d) Indirect relationship exists between Internal and external in changes the biochemical machinery of the cell.

Answer : A

5. Artificial seeds are produced by-
(a) Encapsulating somatic embryos in calcium alginate beads
(b) Desiccating the somatic embryos with or without coating
(c) Hydrating the somatic embryos
(d) Hydrating the zygotic embryos.

Answer : A

6. Being a researcher, you want to improve the deficiency of certain amino acids in cereals and legumes. Choose the technique out of the following which will be the best to achieve your goal:
(a) Plant tissue culture
(b) Adding fertilizers to soil
(c) Protein engineering
(d) Vegetative Propagation

Answer : C

7. Foreign DNA is directly introduced into the recipient cell using a fine micro-syringe to transform it. The probable advantage this provides could be:
a) No specialised equipment required
b) No damage to cells
c) Low transduction rate
d) Precision of delivery

Answer : D

8. A piece of young hypocotyl was cultured in MS medium in a plant tissue culture lab.
This is a type of-
(a) Organ culture
(b) Callus culture
(c) Explant culture
(d) Mass cell culture

Answer : C

9. Molecular Biologists prefer to use artificial vectors with MCS. List a benefit for this choice.
(a) Flexibility in choice of insert size
(b) Flexibility in choice of vector size
(c) Flexibility in choice of host organism
(d) Flexibility in choice of restriction enzyme

Answer : D

10. Native enzyme Subtilisin is inactivated by bleach, in detergents because of oxidation of methionine at position 222. Choose a strategy that will help overcome this problem:
(a) Use Pepsin instead of Subtilisin
(b) Eliminate use of bleach
(c) Substitute another amino acid at position 222
(d) Use Amylase instead of Subtilisin

Answer : C

11. Culture based approaches for detecting pathogens, as compared to PCR based assays are
(a) Faster, safer but less specific
(b) Slower but safer and more specific
(c) Slower, less safe and less specific
(d) Slower, less safe but more specific

Answer : C

12. A 100 Kb DNA fragment has to be cloned in a host cell. Which vector should be used
for this experiment?
a) Plasmid
b) Cosmid
c) BAC
d) Bacteriophage lambda

Answer : C