Question
Nitrous acid is a __________ agent.
Alkylating agent.
Deaminating agent.
Hydroxylating agent.
None of the above
Alkylating agent.
Deaminating agent.
Hydroxylating agent.
None of the above
Hint:
Nitrous acid converts cytosine to uracil and ammonia.
The correct answer is: Deaminating agent.
- Nitrous acid is a deaminating agent
- The deamination is the process of removal of an amino group
- In DNA, the deaminating agent causes removal of nitrogen containing groups (in bases)
- Deamination of bases causes conversion of one base to another base. Example: Cytosine (pyrimidine) is converted to uracil (purine) and ammonia
- The substitution of a pyrimidine to a purine causes change in the base pairing during subsequent replication and transcription process
Nitrous acid also converts adenine to hypoxanthine and guanine to xanthine
Related Questions to study
DNA is sensitive to temperatures above _______.
90o C.
85o C.
95o C.
80o C.
DNA is sensitive to temperatures above _______.
90o C.
85o C.
95o C.
80o C.
Ionizing radiations include:
X- rays.
Alpha rays.
Gamma rays.
All of the above.
Ionizing radiations include:
X- rays.
Alpha rays.
Gamma rays.
All of the above.
Generally, the mutations are:
Harmful.
Dominant.
Recessive.
Useful.
Generally, the mutations are:
Harmful.
Dominant.
Recessive.
Useful.
Which of the following base analogs exhibit tautomerism?
5-bromouracil.
2-aminopurine.
6-mercaptopurine.
- Acycloguanosine
Which of the following base analogs exhibit tautomerism?
5-bromouracil.
2-aminopurine.
6-mercaptopurine.
- Acycloguanosine
Point Mutation is caused by:
Base analogs.
Alkylating agents.
Hydroxylating agents.
Metal ions.
Point Mutation is caused by:
Base analogs.
Alkylating agents.
Hydroxylating agents.
Metal ions.
Examples of base analogs are ________.
Ethidium bromide.
Acridine dyes.
Mustard gas.
5-Bromouracil.
Examples of base analogs are ________.
Ethidium bromide.
Acridine dyes.
Mustard gas.
5-Bromouracil.
Alkyl bases are induced in DNA by which chemical mutagen?
Deaminating agents
Alkylating agents.
Hydroxylating agents.
None of the above.
Alkyl bases are induced in DNA by which chemical mutagen?
Deaminating agents
Alkylating agents.
Hydroxylating agents.
None of the above.
Base analogs are which type of mutagens?
Chemical mutagens.
Physical mutagens.
Biological mutagens.
Natural mutagens.
Base analogs are which type of mutagens?
Chemical mutagens.
Physical mutagens.
Biological mutagens.
Natural mutagens.
Ionizing radiation causes ___________.
Aromatic hydrocarbon DNA adducts.
Increased reactive oxygen species (ROS)-mediated damage.
Base cross-linking.
None of the above.
Ionizing radiation causes ___________.
Aromatic hydrocarbon DNA adducts.
Increased reactive oxygen species (ROS)-mediated damage.
Base cross-linking.
None of the above.
If the mutation occurs in the non-functional part of DNA, then these mutations may remain as _________.
Silent mutations.
Missense mutations.
Non sense mutations.
Point mutations.
If the mutation occurs in the non-functional part of DNA, then these mutations may remain as _________.
Silent mutations.
Missense mutations.
Non sense mutations.
Point mutations.
Mutations are mainly responsible for:
Variations in the living organisms.
Genetic continuity between individual and offspring.
Growing population rate.
Constancy in the organisms.
Mutations are mainly responsible for:
Variations in the living organisms.
Genetic continuity between individual and offspring.
Growing population rate.
Constancy in the organisms.
_______ is the most mutagenic among UV rays.
UV A.
UV B.
UV C.
None of the above.
_______ is the most mutagenic among UV rays.
UV A.
UV B.
UV C.
None of the above.
__________is the degree by which differences are seen in parents and their off-springs.
Heredity.
Inheritance.
Variation.
Recombination.
__________is the degree by which differences are seen in parents and their off-springs.
Heredity.
Inheritance.
Variation.
Recombination.
Physical mutagens include:
UV rays.
X- rays.
Gamma rays.
All of the above.
Physical mutagens include:
UV rays.
X- rays.
Gamma rays.
All of the above.
When a gene pair hides the effect of another gene, the phenomenon is called ____________.
- Dominance
- Segregation
Epistasis
- Mutation
When a gene pair hides the effect of another gene, the phenomenon is called ____________.
- Dominance
- Segregation
Epistasis
- Mutation
