WGU BIOCHEM OA REVIEW
QUESTIONS AND ANSWERS
Autosomal\-\ans✔Males\and\Females\are\equally\affected
Polymerase\Chain\Reaction\(PCR)\-\ans✔The\process\of\copying\DNA\in\the\lab.
What\is\needed\for\Polymerase\Chain\Reaction?\-\ans✔Template\DNA,\Nucleotides\
(dNTPS),\DNA\Polymerase,\and\DNA\Primers.
What\are\the\three\steps\of\a\Polymerase\Chain\Reaction\(PCR)?\-\ans✔Denaturing,\
Annealing,\Elongating
What\is\the\first\step\of\a\Polymerase\Chain\Reaction?\-\ans✔Denaturing\(DNA\is\heated\
up\to\separate\it)
What\is\Annealing?\-\ans✔Cooling\the\Polymerase\Chain\Reaction.\Primers\stick\to\the\
DNA\that\you\want\to\copy\and\ADD\DNA\Polymerase
What\is\elongating?\-\ans✔The\Polymerase\Chain\Reaction\is\heated\and\DNA\
Polymerase\adds\nucleotides\to\build\a\new\DNA\strand.
What\is\NOT\involved\in\PCR?\-\ans✔Ligase
What\is\base\excision\repair\(BER)?\-\ans✔It\is\used\to\repair\damage\to\bases\caused\by\
harmful\molecules\by\removing\the\base\that\is\damaged\and\replacing\it.\#1\
GLYCOSYLASES\see\the\damaged\DNA.\#2\DNA\Polymerase\puts\the\right\one\back\#3\
DNA\Ligase\seals\it.
What\are\the\3\steps\in\base\excision\repair?\-\ans✔DNA\Glycolysase\sees\the\damage\
and\removes\it,\DNA\polymerase\puts\the\tight\base\back,\DNA\ligase\seals\it\back\up.
How\many\nucleotides\does\base\excision\repair\remove?\-\ans✔1
What\is\it\called\when\a\large\section\of\the\nucleotide\is\removed\from\the\DNA\so\that\
DNA\polymerase\can\try\again?\(This\corrects\DNA\damage)\-\ans✔Mismatch\Repair\
(MMR).\It\is\the\only\one\to\occur\during\REPLICATION\-\DURING\THE\
PROOFREADING
, What\repairs\a\base\mismatch?\-\ans✔Mismatch\Repair\(MMR)\repairs\errors\such\as\G\
with\T\instead\of\G\with\C.\DNA\Polymerase\fixes\it.\This\happens\during\replication\and\
MMR\removes\a\large\section\of\the\nucleotide\from\the\DNA\and\DNA\Polymerase\tries\
again.
What\is\DNA\Transcription?\-\ans✔When\DNA\polymerase\takes\an\individual\nucleotide\
and\matches\them\to\the\parental\sequences\to\ensure\a\correct\pair.\(it\must\bind\with\
RNA\primer\to\work).\ie:\DNA\Polymerase\binds\to\DNA\to\make\RNA
What\is\NecleoTIDE\repair\-\ans✔CLEANS\damage\caused\by\things\such\as\UV\rays\
and\repairs\it.\A\large\section\of\nucleotides\are\removed,\including\the\damaged\portion,\
along\with\a\few\on\each\side.\It\is\then\replaced\by\DNA\polymerase.
What\is\Homologous\Recombination?\-\ans✔It\repairs\double\stranded\breaks\(last\effort)\
by\copying\another\strand\of\DNA\and\replacing\it\completely.
What\is\Non-Homologous\Recombintaion?\-\ans✔Another\last\effort\to\repair\a\double\
strand\break\by\putting\the\ends\back\together\before\making\sure\they\are\correctly\
copied.\This\can\lead\to\deletions/insertions\(frameshift\mutations).
What\does\DNA\Polymerase\bind\to\in\order\to\make\RNA\TRANSCRIPTION\DNA\take\
the\individual\nucleotide\and\match\them\to\the\PARENTAL\sequences\to\ensure\a\
correct\pair.\-\ans✔It\must\bind\to\RNA\primer
What\happens\during\RNA\splicing\to\generate\a\mature\RNA\molecule?\-\ans✔introns\
(non-coding\region)\are\removed\and\exons\(coding\region)\joined\to\form\a\contiguous\
coding\sequence.
What\is\Gene\Expression?\-\ans✔The\ability\to\turn\genes\on\and\off
What\is\epigenetics?\-\ans✔The\study\of\changes\in\organisms\caused\by\modification\of\
gene\expression\NOT\alternation\of\the\gene\code.
What\is\packaging\of\DNA?\-\ans✔Where\a\DNA\molecule\wraps\around\histone\proteins\
to\form\tight\loops\called\nucleosomes.\These\nucleosomes\coil\and\stack\together\to\
form\fibers\called\chromatin.\(genes\are\ON\if\the\nucleosomes\are\wide\spread\and\OFF\
if\the\genes\are\tightly\packed)
What\is\needed\for\DNA\replication?\-\ans✔Polymerase
What\is\NonSense\Mutation\-\ans✔A\point\mutation\in\a\sequence\of\DNA\(change\in\one\
nucleotide)\that\results\in\a\premature\STOP\codon
What\is\a\Silent\Mutation?\-\ans✔A\mutations\in\DNA\that\do\not\have\an\observable\
effect\on\the\organism's\phenotype.\(1\neucleotide\changes\but\it\codes\for\the\same\
amino\acid)
QUESTIONS AND ANSWERS
Autosomal\-\ans✔Males\and\Females\are\equally\affected
Polymerase\Chain\Reaction\(PCR)\-\ans✔The\process\of\copying\DNA\in\the\lab.
What\is\needed\for\Polymerase\Chain\Reaction?\-\ans✔Template\DNA,\Nucleotides\
(dNTPS),\DNA\Polymerase,\and\DNA\Primers.
What\are\the\three\steps\of\a\Polymerase\Chain\Reaction\(PCR)?\-\ans✔Denaturing,\
Annealing,\Elongating
What\is\the\first\step\of\a\Polymerase\Chain\Reaction?\-\ans✔Denaturing\(DNA\is\heated\
up\to\separate\it)
What\is\Annealing?\-\ans✔Cooling\the\Polymerase\Chain\Reaction.\Primers\stick\to\the\
DNA\that\you\want\to\copy\and\ADD\DNA\Polymerase
What\is\elongating?\-\ans✔The\Polymerase\Chain\Reaction\is\heated\and\DNA\
Polymerase\adds\nucleotides\to\build\a\new\DNA\strand.
What\is\NOT\involved\in\PCR?\-\ans✔Ligase
What\is\base\excision\repair\(BER)?\-\ans✔It\is\used\to\repair\damage\to\bases\caused\by\
harmful\molecules\by\removing\the\base\that\is\damaged\and\replacing\it.\#1\
GLYCOSYLASES\see\the\damaged\DNA.\#2\DNA\Polymerase\puts\the\right\one\back\#3\
DNA\Ligase\seals\it.
What\are\the\3\steps\in\base\excision\repair?\-\ans✔DNA\Glycolysase\sees\the\damage\
and\removes\it,\DNA\polymerase\puts\the\tight\base\back,\DNA\ligase\seals\it\back\up.
How\many\nucleotides\does\base\excision\repair\remove?\-\ans✔1
What\is\it\called\when\a\large\section\of\the\nucleotide\is\removed\from\the\DNA\so\that\
DNA\polymerase\can\try\again?\(This\corrects\DNA\damage)\-\ans✔Mismatch\Repair\
(MMR).\It\is\the\only\one\to\occur\during\REPLICATION\-\DURING\THE\
PROOFREADING
, What\repairs\a\base\mismatch?\-\ans✔Mismatch\Repair\(MMR)\repairs\errors\such\as\G\
with\T\instead\of\G\with\C.\DNA\Polymerase\fixes\it.\This\happens\during\replication\and\
MMR\removes\a\large\section\of\the\nucleotide\from\the\DNA\and\DNA\Polymerase\tries\
again.
What\is\DNA\Transcription?\-\ans✔When\DNA\polymerase\takes\an\individual\nucleotide\
and\matches\them\to\the\parental\sequences\to\ensure\a\correct\pair.\(it\must\bind\with\
RNA\primer\to\work).\ie:\DNA\Polymerase\binds\to\DNA\to\make\RNA
What\is\NecleoTIDE\repair\-\ans✔CLEANS\damage\caused\by\things\such\as\UV\rays\
and\repairs\it.\A\large\section\of\nucleotides\are\removed,\including\the\damaged\portion,\
along\with\a\few\on\each\side.\It\is\then\replaced\by\DNA\polymerase.
What\is\Homologous\Recombination?\-\ans✔It\repairs\double\stranded\breaks\(last\effort)\
by\copying\another\strand\of\DNA\and\replacing\it\completely.
What\is\Non-Homologous\Recombintaion?\-\ans✔Another\last\effort\to\repair\a\double\
strand\break\by\putting\the\ends\back\together\before\making\sure\they\are\correctly\
copied.\This\can\lead\to\deletions/insertions\(frameshift\mutations).
What\does\DNA\Polymerase\bind\to\in\order\to\make\RNA\TRANSCRIPTION\DNA\take\
the\individual\nucleotide\and\match\them\to\the\PARENTAL\sequences\to\ensure\a\
correct\pair.\-\ans✔It\must\bind\to\RNA\primer
What\happens\during\RNA\splicing\to\generate\a\mature\RNA\molecule?\-\ans✔introns\
(non-coding\region)\are\removed\and\exons\(coding\region)\joined\to\form\a\contiguous\
coding\sequence.
What\is\Gene\Expression?\-\ans✔The\ability\to\turn\genes\on\and\off
What\is\epigenetics?\-\ans✔The\study\of\changes\in\organisms\caused\by\modification\of\
gene\expression\NOT\alternation\of\the\gene\code.
What\is\packaging\of\DNA?\-\ans✔Where\a\DNA\molecule\wraps\around\histone\proteins\
to\form\tight\loops\called\nucleosomes.\These\nucleosomes\coil\and\stack\together\to\
form\fibers\called\chromatin.\(genes\are\ON\if\the\nucleosomes\are\wide\spread\and\OFF\
if\the\genes\are\tightly\packed)
What\is\needed\for\DNA\replication?\-\ans✔Polymerase
What\is\NonSense\Mutation\-\ans✔A\point\mutation\in\a\sequence\of\DNA\(change\in\one\
nucleotide)\that\results\in\a\premature\STOP\codon
What\is\a\Silent\Mutation?\-\ans✔A\mutations\in\DNA\that\do\not\have\an\observable\
effect\on\the\organism's\phenotype.\(1\neucleotide\changes\but\it\codes\for\the\same\
amino\acid)
