Biology
Molecular Genetics
851 Questions
Molecular genetics explores the mechanisms of genetic information transfer, including DNA replication, transcription, and translation. It is a core component of biology syllabi. These concepts frequently appear in general science sections of major competitive exams.
DNA replicationTranscription processTranslation processRNA typesCentral dogma
Molecular Genetics Questions
Which type of gene regulation involves the degradation of mRNA molecules to prevent their translation into proteins?
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Transcriptional regulation
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Translational regulation
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Post-translational regulation
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Gene silencing
B
Correct answer
Explanation
Translational regulation involves the degradation of mRNA molecules to prevent their translation into proteins. This can be achieved through various mechanisms, such as the binding of microRNAs to mRNA or the phosphorylation of translation initiation factors.
Which type of gene regulation involves the modification of proteins after they have been translated from mRNA?
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Transcriptional regulation
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Translational regulation
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Post-translational regulation
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Gene silencing
C
Correct answer
Explanation
Post-translational regulation involves the modification of proteins after they have been translated from mRNA. This can include modifications such as phosphorylation, glycosylation, or ubiquitination, which can affect the protein's activity, stability, or localization.
Which type of gene regulation involves the silencing of gene expression through mechanisms such as DNA methylation or histone modification?
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Transcriptional regulation
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Translational regulation
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Post-translational regulation
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Gene silencing
D
Correct answer
Explanation
Gene silencing involves the silencing of gene expression through mechanisms such as DNA methylation or histone modification. This can lead to the complete or partial inhibition of gene transcription or translation.
What is the central dogma of molecular biology?
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DNA makes RNA makes protein.
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RNA makes DNA makes protein.
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Protein makes DNA makes RNA.
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DNA makes protein makes RNA.
A
Correct answer
Explanation
The central dogma of molecular biology states that DNA is transcribed into RNA, which is then translated into protein.
What is the structure of RNA?
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A double helix.
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A single helix.
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A triple helix.
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A quadruple helix.
B
Correct answer
Explanation
RNA is a single helix, meaning that it consists of only one strand of nucleotides.
What is the process by which DNA is transcribed into RNA?
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Transcription.
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Translation.
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Replication.
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Mutation.
A
Correct answer
Explanation
Transcription is the process by which DNA is transcribed into RNA.
What is the enzyme that catalyzes transcription?
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RNA polymerase.
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DNA polymerase.
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Helicase.
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Ligase.
A
Correct answer
Explanation
RNA polymerase is the enzyme that catalyzes transcription.
What is the process by which RNA is translated into protein?
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Transcription.
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Translation.
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Replication.
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Mutation.
B
Correct answer
Explanation
Translation is the process by which RNA is translated into protein.
What is the enzyme that catalyzes translation?
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Ribosome.
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Transfer RNA.
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Messenger RNA.
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Aminoacyl tRNA synthetase.
A
Correct answer
Explanation
The ribosome is the enzyme that catalyzes translation.
What is the role of tRNA in translation?
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It carries amino acids to the ribosome.
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It binds to the mRNA.
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It catalyzes the formation of peptide bonds.
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It releases the newly synthesized protein.
A
Correct answer
Explanation
tRNA carries amino acids to the ribosome.
What is the role of mRNA in translation?
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It carries amino acids to the ribosome.
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It binds to the tRNA.
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It catalyzes the formation of peptide bonds.
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It releases the newly synthesized protein.
What is the role of the ribosome in translation?
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It carries amino acids to the ribosome.
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It binds to the mRNA.
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It catalyzes the formation of peptide bonds.
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It releases the newly synthesized protein.
C
Correct answer
Explanation
The ribosome catalyzes the formation of peptide bonds.
What is the role of aminoacyl tRNA synthetase in translation?
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It carries amino acids to the ribosome.
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It binds to the mRNA.
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It catalyzes the formation of peptide bonds.
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It releases the newly synthesized protein.
Correct answer
Explanation
Aminoacyl tRNA synthetase attaches amino acids to tRNA.
What is the relationship between DNA, RNA, and protein?
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DNA makes RNA makes protein.
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RNA makes DNA makes protein.
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Protein makes DNA makes RNA.
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DNA makes protein makes RNA.
A
Correct answer
Explanation
The relationship between DNA, RNA, and protein is that DNA makes RNA makes protein.
Which type of RNA is responsible for carrying genetic information from DNA to the ribosome?
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Messenger RNA (mRNA)
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Transfer RNA (tRNA)
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Ribosomal RNA (rRNA)
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Small Nuclear RNA (snRNA)
A
Correct answer
Explanation
mRNA carries the genetic code from DNA to the ribosome for protein synthesis.