Biochemistry II

  1. Define DNA repair.
    • The set of biochemical mechanisms that recognize genomic alterations and
    • replaces those alterations with their correct counterparts.
  2. What is the difference between DNA damage and mutation?
    DNA damage is an alteration that can lead to a mutation, while a mutation is the change in the nucleotide sequence.
  3. What are the two main ways to cause DNA damage?
    Spontaneous change or enviromental conditions
  4. What are the two main types of spontaneous change?
    Deamination and base loss
  5. What can deamination lead to? What can base loss lead to?
    • Deamination can lead to base substitution
    • following the initial replication. Bass loss can lead to a blocking of
    • replication or substiution by the error prone DNA polymerase.
  6. Define karyotype.
    It is a display of the 46 chromosomes, which includes the 2 autosomes (X,X or X,Y).
  7. How are eukaryotes and prokaryotes different, based soley upon RNA polymerase.
    Eukaryotes have 3 RNA polymerases: I= coding for the rRNAs, II= coding for mRNA, III= coding for all other snRNAs including tRNA.Prokaryotes have only one RNA polymerase.
  8. What is done to pre-mRNA before it is called mature?
    The 5' 7-methylguanosine cap must be added and the 250 A residue 3' poly A tail must be added so that it does not get degraded.
Card Set
Biochemistry II