Biology

Molecular Genetics

917 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

Multiple choice

What is the role of RNA in the central dogma?

  1. It carries genetic information from DNA to the ribosome.

  2. It is translated into protein.

  3. It regulates gene expression.

  4. All of the above.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

RNA carries genetic information from DNA to the ribosome, is translated into protein, and regulates gene expression. It is a versatile molecule that plays a key role in many cellular processes.

Multiple choice

What is the process by which DNA is transcribed into RNA called?

  1. Replication

  2. Transcription

  3. Translation

  4. Mutation

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Transcription is the process by which DNA is transcribed into RNA. It is carried out by an enzyme called RNA polymerase, which reads the DNA sequence and synthesizes a complementary RNA molecule.

Multiple choice

What is the process by which RNA is translated into protein called?

  1. Replication

  2. Transcription

  3. Translation

  4. Mutation

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Translation is the process by which RNA is translated into protein. It is carried out by a complex of molecules called the ribosome, which reads the RNA sequence and synthesizes a protein molecule.

Multiple choice

What is the genetic code?

  1. The set of rules that determines how DNA is transcribed into RNA.

  2. The set of rules that determines how RNA is translated into protein.

  3. The set of rules that determines how proteins are folded into their functional shapes.

  4. The set of rules that determines how cells divide.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The genetic code is the set of rules that determines how RNA is translated into protein. It is a universal code that is shared by all living organisms.

Multiple choice

What is a stop codon?

  1. A codon that codes for an amino acid.

  2. A codon that codes for a stop signal.

  3. A codon that codes for a start signal.

  4. A codon that codes for a regulatory element.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A stop codon is a codon that codes for a stop signal. Stop signals are used to terminate protein synthesis.

Multiple choice

What is a start codon?

  1. A codon that codes for an amino acid.

  2. A codon that codes for a stop signal.

  3. A codon that codes for a start signal.

  4. A codon that codes for a regulatory element.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A start codon is a codon that codes for a start signal. Start signals are used to initiate protein synthesis.

Multiple choice

What is the role of tRNA in protein synthesis?

  1. It carries amino acids to the ribosome.

  2. It reads the mRNA sequence.

  3. It synthesizes the protein chain.

  4. It releases the protein from the ribosome.

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

tRNA carries amino acids to the ribosome. Each tRNA molecule is specific for a particular amino acid.

Multiple choice

What is the role of mRNA in protein synthesis?

  1. It carries genetic information from DNA to the ribosome.

  2. It is translated into protein.

  3. It regulates gene expression.

  4. All of the above.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

mRNA carries genetic information from DNA to the ribosome, is translated into protein, and regulates gene expression. It is a versatile molecule that plays a key role in protein synthesis.

Multiple choice

What is the role of the ribosome in protein synthesis?

  1. It reads the mRNA sequence.

  2. It synthesizes the protein chain.

  3. It releases the protein from the ribosome.

  4. All of the above.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The ribosome reads the mRNA sequence, synthesizes the protein chain, and releases the protein from the ribosome. It is a complex molecular machine that is essential for protein synthesis.

Multiple choice

What are the two main types of DNA microarrays?

  1. Oligonucleotide microarrays and cDNA microarrays

  2. Affymetrix microarrays and Illumina microarrays

  3. Spotted microarrays and in situ synthesized microarrays

  4. Microarrays for gene expression analysis and microarrays for genotyping

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The two main types of DNA microarrays are oligonucleotide microarrays, which contain short synthetic DNA probes, and cDNA microarrays, which contain longer DNA fragments derived from cDNA libraries.

Multiple choice

The molecule that carries genetic information in all living organisms is:

  1. DNA

  2. RNA

  3. Protein

  4. Carbohydrate

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DNA (deoxyribonucleic acid) is the molecule that carries genetic information in all living organisms. It is a double-stranded molecule composed of four different types of nucleotides: adenine (A), thymine (T), cytosine (C), and guanine (G).

Multiple choice

The process by which DNA is copied into RNA is called:

  1. Replication

  2. Transcription

  3. Translation

  4. Mutation

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Transcription is the process by which DNA is copied into RNA. It is carried out by an enzyme called RNA polymerase, which reads the DNA sequence and synthesizes a complementary RNA molecule.

Multiple choice

The process by which RNA is used to synthesize proteins is called:

  1. Replication

  2. Transcription

  3. Translation

  4. Mutation

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Translation is the process by which RNA is used to synthesize proteins. It is carried out by ribosomes, which read the RNA sequence and assemble the corresponding amino acids into a protein chain.

Multiple choice

The process by which cells repair damaged DNA is called:

  1. Replication

  2. Transcription

  3. Translation

  4. DNA repair

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

DNA repair is the process by which cells repair damaged DNA. It is carried out by a variety of enzymes, which can repair different types of DNA damage.

Multiple choice

What is the central dogma of molecular biology?

  1. DNA makes RNA makes protein

  2. RNA makes DNA makes protein

  3. Protein makes DNA makes RNA

  4. DNA makes protein makes RNA

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The central dogma of molecular biology states that the information in DNA is transcribed into RNA, which is then translated into protein.