DNA and Gene Expression Practice Test

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• A group of genes that are regulated together because they are all needed at the same time is called what?
• During replication, what is the role of single-strand binding proteins?
• Which statement about histone methylation and acetylation is correct?
• What is CRISPR-Cas9 and what is required for target recognition?
• What is the role of histone acetyltransferases (HATs) in gene regulation?
• Which term denotes the proteins around which DNA winds to form nucleosome-like structures within chromatin?
• Which process produces an RNA molecule from a DNA template?
• Which chromatin configuration is least likely to support transcription?
• A change in the nucleotide sequence of a chromosome is called?
• Name two common post-translational modifications and their general roles?
• Which ribosomal subunits coordinate mRNA decoding and tRNA binding?
• What are Okazaki fragments and on which strand do they occur?
• Which mutation type results in a single base substitution that changes an amino acid?
• How do environmental factors influence gene expression through signal transduction?
• What is the diffuse material in the nucleus composed of DNA and proteins that forms chromosomes?
• What is the purpose of a gene knockout experiment, and which controls are essential?
• Which statement best describes the central dogma of molecular biology?
• Which molecule carries genetic information in cells?
• Which statements correctly define the promoter region and the role of transcription factors in eukaryotic transcription?
• Which repair process directly ligates DNA ends and is more error-prone?
• Which RNA processing steps occur in eukaryotic cells after transcription?
• How does codon degeneracy affect the impact of point mutations in coding regions?
• What does semiconservative replication mean?
• In agarose gel electrophoresis, how do smaller DNA fragments behave compared to larger fragments?
• Which enzyme unwinds the DNA double helix during replication?
• What is the function and location of the TATA box in eukaryotic transcription?
• Distinguish between promoters, enhancers, and silencers in gene regulation.
• Which DNA element serves as the binding site for regulatory proteins to control transcription?
• During PCR, what is the purpose of dNTPs?
• What happens in a frameshift mutation?
• Which enzyme extends telomeres in some cells to counteract shortening?
• Which RNA forms the core of ribosomes and helps read the mRNA?
• How does alternative splicing influence protein diversity?
• In which cell types is telomerase activity typically present?
• What is the role of a promoter in a cloning vector?
• The monomer of the DNA molecule is called a what?
• What is the role of the sigma factor in bacterial transcription?
• Which enzyme removes methyl groups from histone tails?
• During DNA replication, which enzyme is responsible for unwinding the double helix?
• How does CRISPR-Cas9 enable targeted genome editing, and what are common repair outcomes after Cas9-induced double-strand breaks?
• Which mechanism primarily ensures high fidelity during DNA replication?
• A chromatin state characterized by gene silencing and dense packing is called?
• What is the role of the sigma factor in bacterial transcription initiation?
• What is the function of enhancers and promoters in eukaryotic transcription?
• Which enzyme synthesizes RNA primers on the templates during replication?
• Which mutation is described as a chromosome piece reattaching to the original chromosome in reverse orientation?
• Three tRNA nucleotides that have to match the mRNA codon before an amino acid is released?
• What molecules help RNA Polymerase bind to the promoter?
• What is the start codon in the genetic code and which amino acid does it encode?
• Which of the following are short DNA segments synthesized on the lagging strand?
• Which term describes the process of copying DNA?
• Describe the Lac operon regulation in the absence and presence of lactose.
• Which of the following best describes a nonsense mutation?
• Which statement best describes the roles of the 5' cap and 3' poly(A) tail in eukaryotic mRNA?
• Why is proper protein folding critical, and what can happen if misfolded?
• Which enzyme creates an RNA primer for initiation of DNA replication?
• Which molecule complex acts to activate transcription of the lac operon when glucose is scarce?
• What damage does nucleotide excision repair primarily fix?
• What is chromatin remodeling and how does it affect gene expression?
• Which experiment demonstrated the transformation principle using pneumonia bacteria?
• Which statement best describes CRISPR-Cas9?
• Which statement best describes Chargaff's rules?
• Distinguish between an operon and a regulon in prokaryotes.
• Which field studies the molecules that sit on a gene affecting its expression?
• Which statement accurately describes translation termination and stop codon recognition?
• Which statement best describes the roles of microRNAs and long non-coding RNAs?
• In eukaryotic transcription, what is the role of the Kozak consensus sequence?
• Which enzyme connects Okazaki fragments on the lagging strand?
• In cloning a gene into a plasmid, which feature is primarily responsible for plasmid maintenance in dividing cells?
• Short fragments of DNA produced on the lagging strand during DNA replication are called what?
• Histone H3 lysine 9 methylation is commonly associated with which outcome?
• Process that takes place to produce a protein.
• What is the main function of RNA polymerase?
• What process did Griffith's experiments show, where a nonpathogenic bacterial strain is transformed by genetic material from a pathogenic strain?
• Which experiment concluded that DNA is the genetic material in bacteriophages?
• Which term describes a three-nucleotide sequence in DNA that codes for one amino acid?
• Compare Sanger sequencing and next-generation sequencing in terms of throughput, accuracy, and read length.
• Which statement correctly describes DNA strand orientation and synthesis direction?
• How is transcription initiated in eukaryotes?
• An extra random nucleotide gets added to the gene.
• Which statement best describes mRNA decay and a major pathway that shortens mRNA half-life?
• In translation initiation, what does the initiator tRNA do?
• What is the purpose of the multiple cloning site (MCS) in a plasmid?
• How does DNA methylation typically affect gene expression?
• Histone methylation can activate or repress transcription depending on which factor?
• What is the principle that bonds in DNA form specifically between adenine-thymine and guanine-cytosine?
• Which enzyme adds individual nucleotides to the growing DNA molecule during replication?
• What is the term for a virus that infects bacteria?
• Which statement best describes the functional impact of post-translational modifications on proteins?
• What is a basic principle of PCR and why is it useful in analyzing DNA?
• Which statement best describes the role of the sigma factor in bacterial transcription?
• What is the role of DNA glycosylases in base excision repair?
• What sequence of DNA do Activators and Repressors attach to?
• Which genes are described as body plan genes?
• Which statement about promoter elements in bacteria is true?
• Which histone methylation mark is commonly associated with active promoters?
• Which of the following best describes a common consequence of ubiquitination on proteins?
• How can codon usage bias affect protein expression in heterologous expression systems?
• Which chromosomal alteration can create a fusion gene?
• What is the replication fork?
• Which component on tRNA contains the anticodon that pairs with the mRNA codon?
• Histone methylation can repress or activate transcription depending on the residue and methylation state.
• Compare homologous recombination and non-homologous end joining in double-strand break repair.
• A single-stranded nucleic acid that passes out of the nucleus to perform various functions?
• Which statement is NOT a common assumption in microarray experiments?
• Why do gene expression patterns differ across tissues, and what regulatory mechanisms contribute?
• How does GC content influence DNA melting temperature and why?
• A chromatin state characterized by gene silencing and dense packing is called?
• Which statement correctly describes transcription?
• Which statement correctly describes the roles of helicase, primase, DNA polymerase III, and DNA ligase during lagging-strand synthesis in prokaryotes?
• Which RNA carries the genetic code from DNA to the ribosome for protein synthesis?
• Which complex is guided by microRNAs to repress translation or degrade target mRNA?
• Which term denotes a regulatory unit where multiple genes are controlled as a single transcriptional unit?
• Which enzyme links together growing RNA nucleotides using a DNA template?
• Distinguish spontaneous from induced mutations with an example.
• What is a riboswitch and how does it regulate gene expression?
• What are common ethical considerations in human gene editing experiments?
• What happens when a stop codon is encountered during translation?
• A nucleotide is switched with another.
• What is the role of molecular chaperones in protein folding?
• What is the role of chromatin remodeling in gene expression?
• Which of the following is a common type of epigenetic mark?
• Which enzyme relieves torsional strain ahead of the replication fork?
• How do microRNAs differ from siRNAs in function and origin?
• Which proteins form the core around which DNA is wound in chromatin?
• Which pathway shortens mRNA half-life via deadenylation?
• Which sequence correctly describes the order of the three main stages in PCR?
• Body plan genes are known as what?
• Which base pairing forms the guanine-cytosine pair?
• Which statement best describes telomeres and telomerase?
• If amplification is weak in a PCR reaction, which troubleshooting steps are commonly recommended?
• In base excision repair, after the damaged base is removed and the site is processed, which enzymes are primarily responsible for filling the gap and sealing the nick?
• The enzymes that add methyl groups to histones are called?
• A nucleotide is removed from the gene.
• Which mutation results in duplicating a major segment of a chromosome?
• What happens to the poly(A) tail of mRNA during deadenylation?
• What is the three-nucleotide sequence on mRNA that codes for an amino acid called?
• Which element is the DNA region where RNA polymerase initiates transcription by recognizing promoter sequences?
• A nucleotide is removed from the gene.
• In RT-qPCR, what does a Ct value indicate?
• Which RNA carries the genetic code for proteins from genes to ribosomes?
• Which RNA transports amino acids to the ribosome?
• Which term describes a three-nucleotide sequence in RNA that codes for an amino acid?
• What is the typical effect of DNA methylation on gene expression when it occurs in CpG islands?
• Which term refers to the enzyme that unwinds the double helix and facilitates replication?
• The term for a mutation that affects a single nucleotide?
• Which base-pairing rule governs DNA?
• Which statement about the TATA box is correct?
• What is the three-nucleotide sequence on DNA that encodes a single amino acid called?
• What is the role of a selectable marker in cloning?
• What is epigenetics and name two common modifications that influence transcription?
• Which factor can influence mutation rates in a genome?
• Describe the steps of nucleotide excision repair when bulky thymine dimers are formed by UV.
• Which statement defines genotype and phenotype most accurately?
• Which base-pair pairs form the rung pairs in DNA?
• In CRISPR-Cas9 editing, what does PAM stand for?
• Mutation that shifts the 'reading' frame of the genetic message.
• Which statement best distinguishes crossing over from independent assortment?
• How do histone acetylation and histone methylation influence chromatin structure and gene expression?
• What is nonsense-mediated decay and when does it occur?
• In bacteria, what do the -10 and -35 promoter regions signify?
• What is the function of the MSH2-MSH6 complex in eukaryotic mismatch repair?
• Which statement about chromosomal deletions, duplications, and translocations is true?
• An extra nucleotide added to a gene.
• Which are the three stages of translation initiation, elongation, and termination?
• Which parts of mRNA are removed during processing?
• Which enzyme unzips or unwinds the double helix at the replication fork?
• What energy source powers helicase activity to unwind the DNA?
• Process by which a gene produces its product and the product carries out its function.
• What is RNA sequencing (RNA-seq) used for in studying gene expression?
• Which mutation occurs when one part of a chromosome breaks off and attaches to another chromosome?
• Which mutation type shifts the reading frame of the genetic message?
• Which histone modification involves adding methyl groups to histone proteins and affects chromatin compaction?
• Outline the steps of translation initiation in eukaryotes.
• Which statement describes the lagging strand during DNA replication?
• Why are Okazaki fragments necessary during replication?
• What is the purpose of optional tags in expression constructs?
• Which double-strand break repair pathway uses a homologous template for repair?
• What is the two-stranded, spiral structure of DNA called?
• In base excision repair, after a glycosylase creates an abasic site, which enzyme typically processes this site to continue repair?
• Histone methylation can repress or activate transcription depending on which factor?
• Which process involves altering parts of the RNA molecule to produce a specific protein?
• What is the role of tRNA and what is an anticodon?
• Which molecules stop RNA Polymerase from moving down the DNA?
• Which of the following is a common post-translational modification?
• Which histone residue is commonly methylated to mark active promoters?
• Which enzymes remove methyl groups from histones?
• What factors commonly facilitate enhancer-promoter looping to boost transcription?
• Which parts of mRNA are used for coding?
• Which components form the spliceosome and what is its role?
• Which statement best describes epigenetic marks?
• What term refers to the accumulation of mutations in a species over time?
• A large mutation of a major section of a chromosome is called?
• Which class of enzymes adds methyl groups to histones?
• A single nucleotide is replaced by a different one.
• What is a common consequence of a frameshift mutation?
• How does the CAP-cAMP complex influence lac operon expression?
• Which of the following statements describes the function of the MSH2-MSH6 complex in mismatch repair?
• What information does RNA-seq provide that RT-qPCR does not?
• How do microRNAs regulate gene expression?
• Which experiment demonstrated that DNA is the molecule of inheritance?
• How do crossing over events during meiosis contribute to genetic diversity?
• Which enzyme links together the growing chain of RNA nucleotides during transcription using a DNA template?
• What is enhancer-promoter looping in eukaryotic gene regulation?
• Which of the following describes a missense mutation?
• Explain how the lac operon is regulated by lactose and glucose availability.
• How does histone acetylation influence chromatin structure and transcription?
• In chromosomal duplications, what is the primary effect on gene expression?
• Which term describes a virus that infects bacteria?
• Semiconservative replication means that each daughter DNA molecule contains one parental strand and one newly synthesized strand. Which experimental evidence supported this model?
• Which DNA sequence do Activators and Repressors attach to?
• Process of altering parts of the mRNA molecule to code for a specific protein?
• How does linkage analysis help identify disease genes?
• What are the main types of mutation that alter a protein's amino acid sequence?
• Which RNA is a component of ribosomes?
• How do transcription factors and coactivators synergistically regulate transcription?
• Which enzyme seals nicks in the sugar-phosphate backbone after Okazaki fragment synthesis?
• A whole section of a chromosome is copied and put in the chromosome.
• Leading strand is synthesized continuously in the same direction as unwinding; lagging is synthesized discontinuously. Which statement is true?
• Chargaff's rules state that in DNA, the amount of adenine equals thymine, and cytosine equals guanine. Which term describes these rules?
• Which is added to the 3' end of most eukaryotic mRNAs?
• How can epigenetic marks be inherited across generations?
• Telomeres and why important?
• Which mutation type is defined as silent, missense, nonsense, and splice-site mutations; which describes a change that does not alter the amino acid sequence?
• What is base excision repair and which enzyme initiates it?
• Okazaki fragments are formed on the lagging strand because DNA synthesis proceeds in which direction relative to the fork?
• How does alternative splicing contribute to proteome diversity?
• How does mismatch repair maintain genome fidelity?
• Which elements regulate transcription by interacting with promoters to increase or decrease transcription, often located far from promoters?
• Which enzyme adds telomeric repeats to chromosome ends in some cells to maintain telomere length?
• The building block of DNA is called a what?
• Which statement best describes why proper protein folding is essential for cellular function?
• How is the genetic code degenerate and what is wobble base-pairing?
• During DNA replication, what structure is formed as a result?
• How does mRNA processing differ between prokaryotes and eukaryotes?
• Histone methylation changes gene expression by altering which aspect of chromatin?