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Chapter 15
Supplemental Instruction
Iowa State University
Nur
Bio 212
Howell
Sep. 28, 2015
Ch. 15 DNA and the Gene: Synthesis and Repair
Define:
Telomeres
Replication Bubble
Replication Fork
Leading Strand
Lagging Strand
Base pairing
Daughter Strand
Parental Strand
DNA Polymerase
Telomerase
DNA Ligase
Nucleotides
Helicase
SSBPs
Primase
Primer
Replisome
dNTPs
Phosphodiester Bond
Nucleotide Excision Repair
Topoisomerase
Okazaki Fragments
Thymine Dimer
Genes vs. Chromosomes
1. Put the following events in order, starting with a.
a) The DNA double helix is relieved of the twisting forces by the protein _______________.
b) The protein ___________ synthesizes an RNA primer on the leading and lagging strands.
c) The protein ____________ opens and unwinds the double helix.
d) The protein ______________________ joins the Okazaki fragments on the lagging strand.
e) A DNA polymerase protein removes the RNA primer at the beginning of Okazaki
fragments on the lagging strand.
f) DNA polymerase works in ___ to ___ direction to synthesize both the leading and
lagging strands.
g) Single stranded DNA binding proteins (SSBPs) bind the lagging strand.
a





A HEAVY NOTE:
THE LEADING AND THE LAGGING STRANDS ARE SYNTHESIZED AT
THE SAME RATE, EVEN THOUGH ABOVE IT SEEMED LIKE THE LAGGING
STRAND WAS SYNTHESIZED AFTER THE LEADING STRAND.
2. Xeroderma Pigmentosum (XP) is a skin disease in humans – caused by mutations in
the nucleotide repair systems. People with XP are sensitive to UV light because it
damages DNA. What will happen to a cell that is accumulating mutations?