From Gene to Protein
Understanding Gene Expression: From Gene to Protein
Test your knowledge on the fascinating process of gene expression with our quiz! This quiz covers crucial concepts, from the role of tRNA in protein synthesis to the intricacies of RNA processing and mutational impacts.
Questions include:
- Understanding tRNA and anticodons
- The role of spliceosomes in RNA processing
- Factors affecting gene expression
The anticodon of a particular tRNA molecule is
A. Complementary to the corresponding mRNA codon.
B. Complementary to the corresponding mRNA triplet in rRNA.
C. changeable, depending on the amino acid that attaches to the tRNA.
D. catalytic, making the tRNA a ribozyme.
E. The part of tRNA that bonds to a specific amino acid.
Spliceosomes are composed of
A. snRNPs and other proteins.
B. Introns and exons.
C. the RNA transcript and protein.
D. snRNPs and snurps.
E. Polymerases and ligases.
We now know that the one gene-one-enzyme hypothesis is not entirely accurate because
A. All the choices are correct.
B. None of the choices are correct.
C. A single gene codes for a single polypeptide chain, and many enzymes are made up of more than one polypeptide chain.
D. Many genes code for proteins that are not enzymes.
E. Many genes code for RNA molecules that have no enzymatic activity.
Using a mRNA codon table, identify a 5' to 3' sequence of nucleotides in the DNA template strand for an mRNA coding for the polypeptide sequence Phe-Pro-Lys.
A. 5'-AAACCCUUU-3'
B. 5'-UUUGGGAAA-3'
C. 5'-CTTCGGGAA-3'
D. 5'-GAACCCCTT-3'
E. 5'-AAAACCTTT-3'
What type of bonding is responsible for maintaining the shape of the tRNA molecule?
A. Covalent bonding between sulfur atoms
B. Hydrogen bonding between base pairs
C. Peptide bonding between amino acids
D. Ionic bonding between phosphates
E. Van der Waals interactions between hydrogen atoms
A base substitution mutation in a gene sometimes does not result in a different protein. Which of the following factors could account for this?
A. The fact that such mutations are usually accompanied by a complementary deletion
B. The rarity of such mutations
C. The mutation affects only the sequence of amino acids, so the protein stays the same
D. Some amino acids are produced from more than one codon
E. A correcting mechanism that is part of the mRNA molecule
RNA polymerase and DNA polymerase differ in that
A. RNA polymerase does not need to separate the two strands of DNA in order to synthesize an RNA copy, whereas DNA polymerase must unwind the double helix before it can replicate the DNA.
B. RNA polymerase can initiate RNA synthesis, but DNA polymerase requires a primer to initiate DNA synthesis.
C. RNA polymerase binds to single-stranded DNA, and DNA polymerase binds to double-stranded DNA.
D. RNA polymerase uses RNA as a template, and DNA polymerase uses a DNA template.
E. RNA polymerase is much more accurate than DNA polymerase.
Which of the following is not true of a codon?
A. It consists of three nucleotides.
B. It may code for the same amino acid as another codon.
C. It never codes for more than on amino acid.
D. It is the basic unit of the genetic code.
E. It extends from one end of a tRNA molecule.
Choose the answer that has these events of protein synthesis in the proper sequence. 1. An aminoacyl-tRNA binds to the A site. 2. A peptide bond forms between the new amino acid and a polypeptide chain. 3. tRNA leaves the P site, and the P site remains vacant. 4. A small ribosomal subunit binds with mRNA. 5. tRNA translocates to the P site.
A. 4, 1, 2, 5, 3
B. 4, 1, 3, 2, 5
C. 1, 3, 2, 4, 5
D. 2, 4, 5, 1, 3
E. 5, 4, 3, 2, 1
Which of the following mutations would be most likely to have a harmful effect on an organism?
A. A single nucleotide deletion in the middle of an intron
B. A nucleotide-pair substitution
C. A single nucleotide insertion downstream of, and close to, the start of the coding sequence
D. A deletion of three nucleotides near the middle of a gene
E. A single nucleotide deletion near the end of the coding sequence
Which of the following is not true of RNA processing?
A. A primary transcript is often much longer than the final RNA molecule that leaves the nucleus.
B. Exons are cut out before mRNA leaves the nucleus.
C. Ribozymes may function in RNA splicing.
D. Nucleotides may be added at both ends of the RNA.
E. RNA splicing can be catalyzed by spliceosomes.
An extraterrestrial life form is discovered. It has a genetic code much like that of organisms on Earth except that there are five different DNA bases instead of four and the base sequences are translated as doublets instead of triplets. How many different amino acids could be accommodated by this genetic code?
A. 10
B. 5
C. 32
D. 25
E. 64
What enzyme catalyzes the attachment of an amino acid to tRNA?
A. RNA polymerase
B. nuclease
C. ligase
D. aminoacyl-tRNA synthetase
E. ribozymes
During RNA processing, a(n) _____________________ is added to the 3' end of the RNA.
A. 3' untranslated region (UTR)
B. AAUAAA
C. Modified guanine nucleotide (GTP)
D. 5' untranslated region (UTR)
E. Long string of adenine nucleotides
In eukaryotic cells, transcription cannot begin until
A. DNA nucleases have isolated the transcription unit.
B. the DNA introns are removed from the template.
C. the 5' caps are removed from the mRNA.
D. The two DNA strands have completely separated and exposed the promoter.
E. Several transcription factors have bound to the promoter.
A transcription unit that is 8,000 nucleotides long may use 1,200 nucleotides to make a protein consisting of 400 amino acids. This is best explained by the fact that
A. Many noncoding nucleotides are present in mRNA.
B. There is redundancy and ambiguity in the genetic code.
C. Many nucleotides are needed to code for each amino acid.
D. Nucleotides break off and are lost during the transcription process.
E. There are termination exons near the beginning of mRNA.
What are polyribosomes?
A. Aggregations of vesicles containing ribosomal RNA
B. Groups of ribosomes reading a single mRNA simultaneously
C. Ribosomes associated with more than one tRNA
D. Ribosomes containing more than two subunits
E. Multiple copies of ribosomes associated with giant chromosomes
Which component is not directly involved in translation?
A. DNA
B. tRNA
C. ribosomes
D. mRNA
E. GTP
A frameshift mutation could result from
A. Deletion of three consecutive bases.
B. A base substitution only.
C. A base deletion only.
D. Either an insertion or a deletion of a base.
E. A base insertion only.
Which of the following is true for both prokaryotic and eukaryotic gene expression?
A. After transcription, a 3' poly-A tail and a 5' cap are added to mRNA.
B. RNA polymerase binds to the promoter region to begin transcription.
C. The mRNA transcript is the exact complement of the gene from which it was copied.
D. mRNA is synthesized in the 3' to 5' direction.
E. Translation of mRNA can begin before transcription is complete.
{"name":"From Gene to Protein", "url":"https://www.quiz-maker.com/QPREVIEW","txt":"Test your knowledge on the fascinating process of gene expression with our quiz! This quiz covers crucial concepts, from the role of tRNA in protein synthesis to the intricacies of RNA processing and mutational impacts.Questions include:Understanding tRNA and anticodonsThe role of spliceosomes in RNA processingFactors affecting gene expression","img":"https:/images/course7.png"}