BIO 208 Midterm 1 Study Guide questions with answers

BIO 208 Midterm 1 Study Guide questions with answers

Central |Dogma |- |correct |answer |-1. |DNA |can |be |replicated |and |this |is |done |by |DNA |polymerase
2. |DNA |is |transcribed |to |RNA |by |RNA |polymerase. |Transcription |is |the |process |of |copying
|hereditary |information |in |DNA |to |RNA



3. |Messenger |RNA |is |translated |into |proteins |in |ribosomes |by |ribose. |Translation |is |the |process |of
|using |the |information |in |nucleic |acids |to |synthesize |proteins




Exceptions |to |central |dogma |- |correct |answer |-1. |Many |genes |code |for |RNA |molecules |that |do |not
|function |as |mRNAs--they |are |not |translated |into |proteins |(total |RNA |or |tRNA)



2. |In |some |cases, |information |flows |back |from |RNA |back |to |DNA. |This |process |is |called |reverse
|transcription |and |is |facilitated |by |reverse |transcipterase. |The |HIV |virus |works |like |this




One-gene, |one |enzyme |hypothesis |- |correct |answer |-Each |gene |contains |the |information |needed |to
|make |one |enzyme, |thus |when |you |"knock |out" |that |gene, |you |also |effectively |"knock |out" |that

|enzyme




N. |Crass |(experiment |to |test |one |gene |one |enzyme |hypothesis) |- |correct |answer |-Previous |work
|had |shown |that |organisms |synthesize |arginine |in |a |series |of |steps |called |a |metabolic |pathway



1. |Radiation |was |used |to |create |a |large |number |of |mutant |cells. |However, |radiation |is |equally |likely
|to |damage |DNA |and |mutate |genes |in |any |part |of |the |organism's |genome, |and |most |organisms

|have |thousands |or |tens |of |thousands |of |genes



2. |Raised |colonies |of |irradiated |cells |on |a |medium |that |included |arginine |(if |cells |grew, |then |they
|could |still |use |the |arginine, |if |cells |didn't |grow, |then |they |knew |something |other |than |that

|pathway |was |wrong



3. |Transferred |a |sample |of |each |colony |to |a |medium |that |lacked |arginine |(If |an |individual |could
|grow |in |the |presence |of |arginine, |but |failed |to |grow |without |arginine, |they |concluded |it |couldn't

|make |its |own |arginine)



4. |Grew |each |mutant |under |four |different |conditions: |a |normal |media |without |arginine, |a |normal
|medium |supplemented |with |orinthine, |citrulline, |or |arginine |and |saw |which |cells |grew |and |when




Arg1 |(lacked |enzyme |1) |- |correct |answer |-Didn't |grow |on |normal |media
Grew |when |exposed |to |ornithine |only, |citrulline |only, |and |arginine |only


Arg |2 |(lacked |enzyme |2) |- |correct |answer |-Didn't |grow |on |normal |media |or |ornithine |only

, Grew |when |exposed |to |citrulline |only |and |arginine |only


Arg |3 |(lacked |enzyme |3) |- |correct |answer |-Didn't |grow |on |normal |media |or |ornithine |only |or
|citrulline |only



Grew |when |exposed |to |arginine |only


Interpretation |of |these |results |(one |gene, |one |enzyme) |- |correct |answer |-If |a |cell |is |lacking |an
|enzyme |in |a |metabolic |pathway, |and |you |supply |it |with |the |protein |that |it |was |supposed |to |code

|for |or |any |product |that |occurs |later |in |the |pathway, |then |the |cell |can |grow, |if |you |supply |it |with

|either |an |enzyme |or |a |product |that |was |used |previously |in |the |pathway, |it |will |not |grow




Coding/non-template |strand |DNA |- |correct |answer |-The |DNA |strand |whose |base |sequence |is
|complementary |to |the |base |sequence |of |the |RNA |transcript |(although |thymine |replaced |by |uracil)

|It |is |this |strand |that |contains |codons



Presented |in |the |5' |to |3' |direction


Non-coding/template |strand |DNA |- |correct |answer |-The |term |template |strand |refers |to |the
|sequence |of |DNA |that |is |copied |during |the |synthesis |of |mRNA. |Contains |anti-codons



During |transcription, |RNA |polymerase |binds |this |strand, |reads |the |anti-codons |and |transcribes |their
|sequence |to |synthesize |an |RNA |transcript |with |complementary |bases




Wild |Type |cell |- |correct |answer |-A |cell |that |currently |does |not |have |any |mutations


20 |different |amino |acids |- |correct |answer |-Different |combinations |of |bases |could |specify |the |20
|amino |acids, |just |as |different |combinations |of |dots |and |sashes |specify |the |26 |letters |of |the

|alphabet. |A |particular |stretch |of |DNA, |then, |could |obtain |the |information |needed |to |produce |the

|amino |acid |sequence |of |a |particular |polypeptide




A-T/U, |C-G |- |correct |answer |-Complementary |base |pairing |between |A-T/U |and |C-G, |what |allows |for
|DNA |to |have |its |stability |



If |you |had |five |nucleotides, |then |you |wouldn't |be |able |to |ahve |complementary |base |pairings, |which
|would |make |it |so |that |you |couldn't |code |for |anything |because |either |one |nucleotide |wouldn't |be

|attracted |to |the |others, |or |one |nucleotide |would |have |multiple |nucleotides |attracted |to |it, |which

|would |get |rid |of |DNA's |integrity