Biochem 9: The Central Dogma
87 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which bond contributes to the stability of the DNA helix?

  • Ionic interactions
  • Phosphodiester bond
  • Hydrophobic interactions
  • H-bonds (correct)

    • What is the structural unit for packaging DNA?

  • Nucleosome (correct)
  • Histone core
  • H-bond
  • Phosphodiester bond

    • What is the name of the DNA packaging complex composed of DNA and tightly bound proteins?

  • Heterochromatin
  • Nucleosome
  • Euchromatin
  • Chromatin (correct)

    • Which form of chromatin is found when the cell is transcriptionally active?

    <p>Euchromatin</p> Signup and view all the answers

    How many pairs of chromosomes do most human cells have?

    <p>23</p> Signup and view all the answers

    What are the maternal and paternal chromosome pair called?

    <p>Homologous chromosomes</p> Signup and view all the answers

    What is the name for the functional units of heredity?

    <p>Genes</p> Signup and view all the answers

    What is the name of the non-coding sequence of a gene that is removed during splicing?

    <p>Intron</p> Signup and view all the answers

    What percentage of the human genome does not encode protein?

    <p>98.5%</p> Signup and view all the answers

    Which biomolecule is the basis for nucleic acid?

    <p>Nucleotide</p> Signup and view all the answers

    What are the 3 components of a nucleotide?

    <p>Sugar, phosphate, and nitrogenous base</p> Signup and view all the answers

    Which of the 4 bases are purines?

    <p>Adenine and guanine</p> Signup and view all the answers

    Which of the 4 bases are pyrimidines?

    <p>Thymine and cytosine</p> Signup and view all the answers

    Why does A always pair with T & G always pair with C?

    <p>It is determined by hydrogen bonding</p> Signup and view all the answers

    Chargaff’s rule states that the number of purines must equal the number of pyrimidines. Why is this necessary to maintain the DNA double helix?

    <p>To ensure stability of the DNA molecule</p> Signup and view all the answers

    What forces are needed to stabilize the DNA double helix?

    <p>Hydrogen bonds between bases</p> Signup and view all the answers

    What is the structure of DNA?

    <p>Double helix</p> Signup and view all the answers

    How many base pairs are there in one complete turn of the DNA double helix?

    <p>10</p> Signup and view all the answers

    What is the role of RNA in the central dogma of molecular biology?

    <p>Act as an intermediate between DNA and protein synthesis</p> Signup and view all the answers

    Which of the following is NOT a chemical difference between RNA and DNA?

    <p>Double-stranded helix structure</p> Signup and view all the answers

    Which type of RNA serves as a template for protein translation?

    <p>mRNA</p> Signup and view all the answers

    What is the term for the RNA molecule initially transcribed from DNA?

    <p>Pre-mRNA</p> Signup and view all the answers

    Which type of non-coding RNA is involved in splicing?

    <p>snRNA</p> Signup and view all the answers

    Which type of RNA is needed for the basic structure of the ribosome complex?

    <p>rRNA</p> Signup and view all the answers

    What is the general term for RNA that serves as enzymatic, structural, and regulatory components in the cell?

    <p>Non-coding RNA</p> Signup and view all the answers

    Which type of RNA forms small nuclear ribonucleoproteins (snRNPs) in the spliceosome?

    <p>snRNA</p> Signup and view all the answers

    Which of the following RNA molecules is involved in catalyzing the peptide bond between amino acids?

    <p>rRNA</p> Signup and view all the answers

    What is the term for the process of removing introns from pre-mRNA?

    <p>Splicing</p> Signup and view all the answers

    Which of the following is NOT a structural difference between RNA and DNA?

    <p>Adenine, guanine, and cytosine content</p> Signup and view all the answers

    Which type of RNA molecule is responsible for carrying the correct amino acid to the growing polypeptide chain during translation?

    <p>tRNA</p> Signup and view all the answers

    What is the function of the anticodon region in tRNA?

    <p>It pairs with the complementary codon in an mRNA molecule</p> Signup and view all the answers

    Which hypothesis explains why there are only 20 amino acids despite 64 possible combinations of nucleotides in a 3 nucleotide codon?

    <p>Wobble hypothesis</p> Signup and view all the answers

    Which region of the tRNA molecule binds the amino acid that corresponds to the anticodon?

    <p>Amino acid binding site</p> Signup and view all the answers

    Which type of RNA molecule regulates gene expression by blocking translation of specific mRNAs and promoting their degradation?

    <p>miRNA</p> Signup and view all the answers

    Which type of RNA molecule reduces gene expression by directly degrading specific mRNA molecules?

    <p>siRNA</p> Signup and view all the answers

    Which type of RNA molecule can increase or decrease transcription and is involved in X-chromosome inactivation?

    <p>lncRNA</p> Signup and view all the answers

    Which type of RNA molecule is an adaptor between mRNA and amino acids and is involved in splicing of pre-mRNA?

    <p>snRNA</p> Signup and view all the answers

    Which type of RNA molecule codes for proteins?

    <p>mRNA</p> Signup and view all the answers

    Which type of RNA molecule is an important constituent of ribosomes and catalyzes protein synthesis?

    <p>rRNA</p> Signup and view all the answers

    Which enzyme is responsible for transcription?

    <p>RNA polymerase</p> Signup and view all the answers

    What is the direction in which RNA polymerase moves during transcription?

    <p>5' to 3'</p> Signup and view all the answers

    Which region of a gene contains the consensus sequence and specifies the start of transcription?

    <p>Promoter region</p> Signup and view all the answers

    What is the role of transcription initiation factors in the process of transcription?

    <p>They help RNA polymerase recognize the template strand</p> Signup and view all the answers

    What are the three main stages of transcription?

    <p>Initiation, elongation, termination</p> Signup and view all the answers

    Which of the following is NOT a processing step during transcription in eukaryotes?

    <p>Polymerization of RNA</p> Signup and view all the answers

    Which enzyme is responsible for synthesizing an RNA molecule from a DNA template during transcription?

    <p>RNA polymerase</p> Signup and view all the answers

    What are the steps of transcription in the correct order?

    <p>Initiation, elongation, processing, termination</p> Signup and view all the answers

    Which type of RNA molecule carries the correct amino acid to the growing polypeptide chain during translation?

    <p>tRNA</p> Signup and view all the answers

    What are the steps of translation in the correct order?

    <p>Initiation, elongation, termination</p> Signup and view all the answers

    Which molecule is responsible for catalyzing the peptide bond between amino acids during translation?

    <p>rRNA</p> Signup and view all the answers

    How are proteins targeted to a cellular location during translation?

    <p>By signal sequences</p> Signup and view all the answers

    What is the function of the Shine-Dalgarno sequence?

    <p>Needed in binding initiation of small ribosomal subunit</p> Signup and view all the answers

    Which of the following is NOT a role of elongation factors in translation?

    <p>Binding to the stop codon</p> Signup and view all the answers

    What happens during termination in translation?

    <p>All of the above</p> Signup and view all the answers

    What is the first amino acid added to any polypeptide?

    <p>Methionine</p> Signup and view all the answers

    Which of the following describes the correct order of translation initiation in eukaryotes?

    <p>Small ribosomal subunit binds to the 5’ cap and scans the mRNA until it reaches AUG, then Met-tRNAi binds to the P site</p> Signup and view all the answers

    During transcription, which of the following proteins bind the TATA box within the promoter region?

    <p>TFII D</p> Signup and view all the answers

    Which of the following are CORRECT regarding RNA processing?

    <p>Splicing is catalyzed by snRNA and proteins complexed into snRNPs</p> Signup and view all the answers

    What might happen if a nucleotide was accidentally inserted into the middle of a gene?

    <p>The gene would produce a completely different protein</p> Signup and view all the answers

    Which of the following is TRUE about the mRNA transcript produced in prokaryotes?

    <p>It can begin translation right away</p> Signup and view all the answers

    What is the role of the 5’ cap in mRNA processing?

    <p>It is involved in translation</p> Signup and view all the answers

    What is the role of the Poly A tail in mRNA processing?

    <p>It protects the 3’ end of the mRNA from degradation</p> Signup and view all the answers

    Which of the following is true about protein synthesis in prokaryotes?

    <p>The small ribosomal subunit binds to the Shine Dalgarno sequence</p> Signup and view all the answers

    Which of the following is true about protein synthesis in eukaryotes?

    <p>The small ribosomal subunit binds to the 5' cap and scans the mRNA until it reaches the start codon</p> Signup and view all the answers

    What happens after a protein is fully translated?

    <p>All of the above</p> Signup and view all the answers

    What is the role of polysomes in protein synthesis?

    <p>To speed up the rate of protein synthesis</p> Signup and view all the answers

    Which of the following is a clinical application of understanding protein synthesis?

    <p>All of the above</p> Signup and view all the answers

    What is the purpose of the Shine Dalgarno sequence in prokaryotic protein synthesis?

    <p>To bind the small ribosomal subunit to the mRNA</p> Signup and view all the answers

    Which of the following is NOT a way a cell can regulate the amount of a particular protein available to a cell?

    <p>Location of the protein</p> Signup and view all the answers

    Which of the following is true about histone acetylation?

    <p>It is carried out by histone acetyltransferases (HAT)</p> Signup and view all the answers

    What is the function of histone methylation?

    <p>It promotes transcriptional activation</p> Signup and view all the answers

    Which of the following is NOT a way mRNA stability can be regulated?

    <p>Histone modification can stabilize mRNA</p> Signup and view all the answers

    What is the relationship between the stability of mRNA and protein synthesis?

    <p>The longer an mRNA lasts in the cytosol, the more protein will be made</p> Signup and view all the answers

    What is the role of chromatin remodeling complexes in transcription regulation?

    <p>They reposition nucleosomes on DNA</p> Signup and view all the answers

    What is the role of histone modifications in transcription regulation?

    <p>They increase transcription</p> Signup and view all the answers

    Which of the following is true about DNA methylation?

    <p>It typically results in transcriptional silencing</p> Signup and view all the answers

    What is the function of non-coding forms of RNA, such as miRNA or siRNA?

    <p>They promote mRNA destruction</p> Signup and view all the answers

    Which of the following is true about histones?

    <p>They are highly dynamic structures regulated by nuclear proteins</p> Signup and view all the answers

    Which of the following is false about targeting proteins to the rough ER for translation?

    <p>Translation of proteins destined for the rough ER occurs in the mitochondria.</p> Signup and view all the answers

    What happens when a protein containing a stop transfer sequence comes into contact with the translocator during translation?

    <p>Translation is paused and the translocator discharges the polypeptide into the cytosol.</p> Signup and view all the answers

    Which of the following is true about the amino acids in the stop transfer sequence?

    <p>They are nonpolar.</p> Signup and view all the answers

    Which region of the tRNA molecule binds the amino acid that corresponds to the anticodon?

    <p>Acceptor stem</p> Signup and view all the answers

    What is the function of the signal recognition particle (SRP) in protein targeting to the rough ER?

    <p>To direct the ribosome to the rough ER</p> Signup and view all the answers

    Which of the following is true about the targeting of proteins to the nucleus, mitochondria, or peroxisomes during translation?

    <p>Proteins are translated on free ribosomes in the cytosol.</p> Signup and view all the answers

    What is the role of the stop transfer sequence in protein targeting during translation?

    <p>To pause translation</p> Signup and view all the answers

    Which of the following is true about the targeting of proteins to lysosomes, ER, cell membrane, or secretion during translation?

    <p>A signal peptide sequence is translated, which binds a signal recognition particle (SRP).</p> Signup and view all the answers

    Match the events of translation to the steps they occurs in:

    <p>Initiation = AUG (methionine) marks the start of the codon and the small ribosomal units bind with a 5' end of mRNA Elongation = tRNA binding, Peptide bond formation, Large subunit translocation, Small subunit translocation Termination = Stop codons UAA, UAG, UGA marks the end of a peptide, peptidyl transferase catalyzes the reaction with water releasing the COOH group Translation = The mRNA has been brought out of the nucleus and into the cytosol where protein synthesis can occur</p> Signup and view all the answers

    More Like This

    Biochem Chapter 5 - Properties of Enzymes
    63 questions

    Biochem Chapter 5 - Properties of Enzymes

    CalmingCornet avatar
    CalmingCornet
    BioChem C785 Carbohydrates and ATP Flashcards
    77 questions

    BioChem C785 Carbohydrates and ATP Flashcards

    LavishDiopside625 avatar
    LavishDiopside625
    Biochem Review 8 Flashcards
    15 questions

    Biochem Review 8 Flashcards

    BeneficialThermodynamics avatar
    BeneficialThermodynamics
    BIOCHEM Chapter 12 Flashcards
    10 questions

    BIOCHEM Chapter 12 Flashcards

    SolicitousPelican7010 avatar
    SolicitousPelican7010
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser