Module Exam #2

Last update by harmon.271 on 06/08/2011
48646 People have viewed this Quiz
  • Share

What happens to a chromosome that loses it centromere?

Answer:
There would be no site for the attachment of spindle microtubules, and so no separation of chromosomes during mitosis or meiosis. The chromosome is usually lost.

View Module Exam #2 as Flashcard Deck

Related Quiz Content
  • harmon 271
    Answered in Module Exam #2
    Two double-stranded fragments of DNA are exactly the same length. At 89°C, fragment A has completely denatured, which means that the two strands have separated. At that temperature, fragment B is still double-stranded. How might these fragments differ, to result in different denaturation temperatures?
    Fragment B has a higher percentage of G-C pairs and requires a higher melting temperature. G-C are held together by three hydrogen bonds.
  • harmon 271
    Answered in Module Exam #2

    1. How did the work of Hershey and Chase contribute to the model of DNA as the genetic material?

    Hershey and Chase designed a series of experiments to determine whether phage protein or DNA is transmitted in phage replication. They used radioactive forms of phosphorus and sulfur to follow DNA and protein. When new phage progeny emerged, many emitted radioactivity from 32P, demonstrating that DNA had been passed on during reproduction.
  • harmon 271
    Answered in Module Exam #2

    1. Explain at least two reasons why the following definition of a gene is inadequate: “A gene consists of DNA sequences that are transcribed into a single RNA molecule that encodes a single polypeptide.”

    1) A single gene can encode for more than one protein through alternative splicing.
    2) DNA can be transcribed multiple times into RNA molecules.
  • harmon 271
    Answered in Module Exam #2

    Why do eukaryotic chromosomes have multiple origins of replication, whereas prokaryotic chromosomes typically have only one origin?

    prokaryotes' circular DNA is limited in size and so replication at a single site can form new strands in a reasonable amount of time. large linear eukaryotic chromosomes, however, contain far too much DNA to be replicated readily from a single origin

  • harmon 271
    Answered in Module Exam #2

    What is semiconservative replication?

    Replication in which each of the original nucleotide strands remain intact, despite no longer being combined in the same molecule. The original DNA molecule is half conserved during replication. Each strand serves as a template for synthesis of a new strand. One new stand and one original strand.
  • harmon 271
    Answered in Module Exam #2
    The bonds that connect nucleotides in a strand are called ___ bonds
    phosphodiester
  • harmon 271
    Answered in Module Exam #2
    This short piece of RNA is present only transiently in a newly-synthesized DNA molecule
    RNA primer
  • harmon 271
    Answered in Module Exam #2
    DNA gyrase
    supercoil removal (reduces torsional strain that builds ahead of the replication fork as a result of unwinding)
  • harmon 271
    Answered in Module Exam #2
    Okazaki fragments
    lagging strand
  • harmon 271
    Answered in Module Exam #2
    Write the anticodon, with correct polarity, of all tRNAs that will bind to the mRNA codon 5' UCG 3', considering wobble-base pairing rules.
    3' AGC 5'
  • harmon 271
    Answered in Module Exam #2
    This new strand has its 3' end oriented in the opposite direction as that in which the replication fork travels.
    Lagging strand