Basic
What is the central dogma of molecular biology?
a) DNA → RNA → Protein
b) RNA → DNA → Protein
c) DNA → Protein → RNA
d) Protein → RNA → DNA
a) DNA → RNA → Protein
What role does the promoter region play in transcription?
a) It terminates transcription.
b) It signals where transcription begins.
c) It helps in RNA splicing.
d) It stabilizes the mRNA.
b) It signals where transcription begins.
Which codon signals the start of translation?
a) UGA
b) AUG
c) UAG
d) UAA
b) AUG
How do prokaryotic RNA polymerases differ from eukaryotic ones?
a) Prokaryotic RNA polymerase requires transcription factors.
b) Prokaryotic RNA polymerase can initiate transcription on its own.
c) Eukaryotic RNA polymerase is less complex.
d) Prokaryotic RNA polymerase binds to ribosomes directly.
b) Prokaryotic RNA polymerase can initiate transcription on its own.
What experiment could you use to test translation accuracy?
a) Alter mRNA codons and analyze the resulting protein sequence.
b) Add introns to mRNA and observe ribosome activity.
c) Block RNA polymerase and measure DNA synthesis.
d) Remove tRNAs and measure RNA stability.
a) Alter mRNA codons and analyze the resulting protein sequence.
Which enzyme is responsible for transcription?
b) RNA polymerase
Which process involves removing introns from pre-mRNA?
a) Transcription
b) Translation
c) RNA splicing
d) Polyadenylation
c) RNA splicing
What might happen if a stop codon were missing?
Translation would continue indefinitely.
What is a spliceosome composed of?
a) DNA and RNA polymerase
b) tRNA and ribosomes
c) snRNPs and proteins
d) Introns and exons
c) snRNPs and proteins
Which feature allows ribosomes to translate multiple proteins simultaneously?
Polyribosomes (polysomes)
What nucleotide is found in RNA but not DNA?
c) Uracil
What is the primary function of tRNA?
a) To transfer RNA molecules into the nucleus
b) To carry amino acids to the ribosome during protein synthesis
c) To regulate gene expression
d) To synthesize RNA from a DNA template
b) To carry amino acids to the ribosome during protein synthesis
Which sequence is likely to be found in a TATA box?
a) ATGC
b) GCAT
c) TATAAA
d) AGCT
c) TATAAA
Which structure signals the end of transcription?
Terminator
What would happen if the poly-A tail of mRNA were removed?
mRNA stability would decrease.
What is the function of mRNA?
a) To splice out introns
b) To carry genetic information from DNA to the ribosome
c) To link amino acids during protein synthesis
d) To form the structural core of ribosomes
b) To carry genetic information from DNA to the ribosome
What feature of mRNA protects it from degradation?
a) Sigma factor
b) Poly-A tail
c) Introns
d) tRNA attachment
b) Poly-A tail
What happens if RNA polymerase cannot bind to the promoter?
Transcription will not begin.
How does alternative splicing contribute to protein diversity?
a) By producing multiple mRNAs from one gene
b) By altering the DNA sequence
c) By preventing translation
d) By adding more introns
a) By producing multiple mRNAs from one gene
Which molecule marks proteins for degradation in proteasomes?
Ubiquitin
Which of the following is NOT a type of RNA?
a) tRNA
b) mRNA
c) sRNA
d) rRNA
c) sRNA
What is the reading frame?
a) The sequence of codons between the start and stop codons
b) The three-dimensional structure of a ribosome
c) The nucleotide sequence of introns
d) The binding site for RNA polymerase
a) The sequence of codons between the start and stop codons
Which type of RNA forms the catalytic core of ribosomes?
a) mRNA
b) tRNA
c) rRNA
d) miRNA
c) rRNA
Why is RNA less stable than DNA?
Rna is single-stranded and has ribosome.
How could you differentiate prokaryotic from eukaryotic transcription?
a) By identifying introns in the RNA
b) By detecting ribosome binding
c) By measuring protein stability
d) By observing translation in the cytoplasm
a) By identifying introns in the RNA