BIO writing assigment 2

  1. what is a histone composed of
    H3-H4 tetramer, 2 H2A-H2B dimers
  2. what does histone H1 do
    helps the nucleosomal DNA compact
  3. what is a nucleosome
    the histone and the DNA wrapped around it
  4. what is a chromatin
    a group of histones and the DNA wrapped around them
  5. what does ATP-dependent chromatin-remodeling complexes do
    Convert ATP to ADP through hydrolysis to contract or loosen chromatin
  6. what is a histone fold
    three alpha helices
  7. what is euchromatin
    less condensed segments of chromatin that is open and active
  8. what is heterochromatin
    more condensed segments of chromatin that is closed and inactive
  9. what happens in Position effect variegation
    the barrier between euchromatin and heterochromatin is flipped allowing the heterochromatin to spread to the euchromatin
  10. what effect does Methylation have on the histone
    it associates more with the other histones, making it less accessible
  11. what effect does acetylation have on the histone
    it assocates less with other histones making it more accesible
  12. what does reader protein complexes do
    recognize covalent modifications on histones allowing another protein to bind to the reader to enable transcription or r
  13. how are histone modfications named
    histone (H3,H4), amino acid changed (K,G,) placement of amino acid(3,4,5), change, (AC, ME3, ME)
  14. how does hetrochromatin spread
    reader writer complex attaches to heterochromatin and spreads until it reaches barrier DNA
  15. how is hetrochromatin inherited through epigenetic inheritance
    hetrochromatin will stay within the barrier DNA causing it to spread within the barrier DNA forming the same stretch hetrochromatin
  16. what does HP1 do
    causes the histones to gel together
  17. what does Cohesin do
    forms the first loops
  18. what does Condensin 2 do
    makes the loops formed by cohesin larger and larger
  19. what does condensin 1 do
    form loops in the loops formed by cohesin and condensin 2
  20. what does the sliding clamp do
    prevents the DNA polymerase from falling off the DNA
  21. how does DNA polymerase proofread it's own work
    if the nucleotide added is wrong, it will take longer to bind and will instead leave before it's binded, if the wrong one is binded, it will drift to the editing site where it is removed
  22. what happens when the DNA polymerase finishes the ozaki fragment
    leaves, then the previous RNA primer is removed by nucleases and replaced with DNA by repair DNA polymerase
  23. what does DNA ligase do to okazaki fragments
    attaches ATP to the 5 prime phosphate, causing it to leave as AMP and for the 5 prime and 3 prime phosphate to bind together, making a continues loop
  24. what does DNA helicase do
    converts ATP to ADP so it can separate the two strands of DNA
  25. what does Single-strand DNA-binding proteins do
    binds to DNA split by the helicase so it can not form hairpins by binding with itself
  26. what does DNA polymerase ε(epsilon) do
    replication of the leading strand
  27. what does DNA polymerase α(alpha) aka primase do
    makes the RNA primers
  28. what does DNA polymerase δ(delta) do
    replication of the lagging strand
  29. how does Strand-directed mismatch repair work
    MutS protein locks onto a mismatched DNA, then recuits MutL to scan DNA until it reaches a sliding clamp and removes the strand, the strand is then repaired by DNA polymerase delta
  30. what does DNA topoisomerases
    helps relive torsional stress by breaking and reforming bonds
  31. what is the replication origin
    place where DNA is first split because it is AT rich which is weaker
  32. what happens to histones during replciation
    the H3-H4 tetramer attaches equally to the new two strands while the H2A-H2B dimers leave
  33. what does telomerase do
    uses RNA to extend the telomere or ends of the DNA strand
  34. when does DNA replciation happen
    in the S phase
  35. what does the FACT protein do
    takes the H3-H4 proteins from the histones from the DNA being split by the heliocase and places it on to the two new strands of DNA
Author
Anthill
ID
365783
Card Set
BIO writing assigment 2
Description
lecture 6, 7, 8, 9
Updated