#1
Which molecule is considered as the 'building block' of nucleic acids?
Amino acid
Monosaccharide
Nucleotide
Fatty acid
#2
Which of the following bases is not found in RNA?
Adenine
Cytosine
Thymine
Uracil
#3
Which of the following represents the central dogma of molecular biology?
DNA → RNA → Protein
RNA → DNA → Protein
Protein → DNA → RNA
Protein → RNA → DNA
#4
Which of the following is not a type of RNA involved in gene expression?
Messenger RNA (mRNA)
Ribosomal RNA (rRNA)
Transfer RNA (tRNA)
Deoxyribosomal RNA (drRNA)
#5
Which of the following is a post-transcriptional modification of mRNA?
Polyadenylation
Translation
Transcription
Promoter binding
#6
Which enzyme is responsible for adding nucleotides to the growing RNA chain during transcription?
RNA polymerase
DNA polymerase
Helicase
Ligase
#7
What is the function of DNA polymerase during DNA replication?
Adds nucleotides to the growing DNA strand
Unwinds the DNA double helix
Replaces RNA primers with DNA nucleotides
Proofreads and corrects errors in DNA replication
#8
In eukaryotic cells, where does transcription occur?
Nucleus
Cytoplasm
Mitochondria
Endoplasmic reticulum
#9
What is the primary function of messenger RNA (mRNA) in the process of protein synthesis?
Carries amino acids to the ribosome
Serves as a template for protein synthesis
Transfers genetic information from DNA to the ribosome
Facilitates the binding of tRNA to the ribosome
#10
Which enzyme is responsible for unwinding the DNA double helix during transcription?
DNA polymerase
Helicase
RNA polymerase
Ligase
#11
What is the function of a promoter sequence in gene expression?
Initiates translation
Determines the location of introns
Regulates the rate of transcription initiation
Facilitates mRNA splicing
#12
Which of the following is an example of a silent mutation?
Substitution of one amino acid for another
Insertion of a stop codon
Deletion of a nucleotide causing a frameshift
Substitution of a nucleotide with no change in amino acid sequence
#13
Which of the following is a function of transfer RNA (tRNA)?
Transfers amino acids to the ribosome
Forms the backbone of the DNA double helix
Facilitates mRNA splicing
Initiates translation by binding to the mRNA start codon
#14
What is the role of ribosomal RNA (rRNA) in translation?
Catalyzes peptide bond formation between amino acids
Binds to the mRNA start codon
Transfers amino acids to the ribosome
Forms the structural and functional components of ribosomes
#15
What is the role of the Shine-Dalgarno sequence in prokaryotic translation?
Initiates translation
Marks the termination codon
Facilitates ribosomal binding to mRNA
Determines the location of introns
#16
What is the function of the polyadenylation signal sequence in eukaryotic mRNA processing?
Initiates translation
Marks the termination codon
Facilitates ribosomal binding to mRNA
Adds a poly(A) tail to the mRNA
#17
What is the significance of alternative splicing in eukaryotic gene expression?
It allows for the production of multiple protein isoforms from a single gene
It prevents transcription from occurring
It initiates translation
It marks the termination codon
#18
What is the function of the spliceosome?
Adds a poly(A) tail to mRNA
Facilitates mRNA splicing
Initiates translation
Catalyzes peptide bond formation