BIO 208 Exam 4 with verified answers
Enzyme |that |synthesizes |DNA |- |correct |answer |-DNA |polymerase
DNA |adds |nucleotides |to |the |- |correct |answer |-3' |end
Bacterial |genes |are |often |organized |as |- |correct |answer |-operons
Operons |are |- |correct |answer |-groups |of |genes |that |are |controlled |by |the |same |promoter
Repressors |are |- |correct |answer |-the |most |commonly |used |form |of |regulation
The |lac |operon |is |an |example |of |an |- |correct |answer |-inducible |operon
Repressor |(l) |gene |is |- |correct |answer |-always |expressed
The |product |of |the |repressor |gene |is |an |- |correct |answer |-active |repressor
The |active |repressor |binds |to |the |operator |and |keeps |the |operon |- |correct |answer |-off
If |lactose |is |present |it |binds |the |repressor |and |- |correct |answer |-inactivates
the |inactivated |repressor |releases |the |operator |and |the |operon |is |now |- |correct |answer |-on
allactose |(effector) |attaches |to |the |- |correct |answer |-repressor
the |tryptophan |operon |is |a |- |correct |answer |-repressible |operon
The |repressor |gene |is |- |correct |answer |-always |expressed
, the |product |of |the |repressor |gene |is |an |- |correct |answer |-inactive |repressor
Tryptophan |is |typically |used |- |correct |answer |-in |protein |synthesis
Mutations |are |- |correct |answer |-changes |in |the |sequence |of |bases |in |DNA
When |one |base |is |substituted |with |another |it |is |a |- |correct |answer |-point |or |base |substitution
When |one |or |more |bases |are |added |to |the |sequence |of |DNA |it |is |an |- |correct |answer |-insertion
When |one |or |more |bases |are |deleted |from |the |sequence |of |DNA |we |have |a |- |correct |answer |-
deletion
The |non-mutated |gene/protein |is |usually |called |- |correct |answer |-wild-type
A |spontaneous |mutation |- |correct |answer |-causes |the |production |of |a |mutated |protein
A |reverse |mutation |- |correct |answer |-occurs |when |a |mutant |gene |undergoes |another |spontaneous
|mutation |which |leads |to |the |production |of |wild-type |protein
silent |mutation |- |correct |answer |-alters |a |base |but |does |not |change |the |amino |acid
nonsense |mutation |- |correct |answer |-A |mutation |that |changes |an |amino |acid |codon |to |one |of |the
|three |stop |codons, |resulting |in |a |shorter |and |usually |nonfunctional |protein.
missense |mutation |- |correct |answer |-A |base-pair |substitution |that |results |in |a |codon |that |codes |for
|a |different |amino |acid.
Deletions/insertions |are |usually |- |correct |answer |-frameshift |mutations
UV |light |causes |the |formation |of |- |correct |answer |-pyrimidine |dimers |which |can |cause |mistakes
|during |DNA |replication
Enzyme |that |synthesizes |DNA |- |correct |answer |-DNA |polymerase
DNA |adds |nucleotides |to |the |- |correct |answer |-3' |end
Bacterial |genes |are |often |organized |as |- |correct |answer |-operons
Operons |are |- |correct |answer |-groups |of |genes |that |are |controlled |by |the |same |promoter
Repressors |are |- |correct |answer |-the |most |commonly |used |form |of |regulation
The |lac |operon |is |an |example |of |an |- |correct |answer |-inducible |operon
Repressor |(l) |gene |is |- |correct |answer |-always |expressed
The |product |of |the |repressor |gene |is |an |- |correct |answer |-active |repressor
The |active |repressor |binds |to |the |operator |and |keeps |the |operon |- |correct |answer |-off
If |lactose |is |present |it |binds |the |repressor |and |- |correct |answer |-inactivates
the |inactivated |repressor |releases |the |operator |and |the |operon |is |now |- |correct |answer |-on
allactose |(effector) |attaches |to |the |- |correct |answer |-repressor
the |tryptophan |operon |is |a |- |correct |answer |-repressible |operon
The |repressor |gene |is |- |correct |answer |-always |expressed
, the |product |of |the |repressor |gene |is |an |- |correct |answer |-inactive |repressor
Tryptophan |is |typically |used |- |correct |answer |-in |protein |synthesis
Mutations |are |- |correct |answer |-changes |in |the |sequence |of |bases |in |DNA
When |one |base |is |substituted |with |another |it |is |a |- |correct |answer |-point |or |base |substitution
When |one |or |more |bases |are |added |to |the |sequence |of |DNA |it |is |an |- |correct |answer |-insertion
When |one |or |more |bases |are |deleted |from |the |sequence |of |DNA |we |have |a |- |correct |answer |-
deletion
The |non-mutated |gene/protein |is |usually |called |- |correct |answer |-wild-type
A |spontaneous |mutation |- |correct |answer |-causes |the |production |of |a |mutated |protein
A |reverse |mutation |- |correct |answer |-occurs |when |a |mutant |gene |undergoes |another |spontaneous
|mutation |which |leads |to |the |production |of |wild-type |protein
silent |mutation |- |correct |answer |-alters |a |base |but |does |not |change |the |amino |acid
nonsense |mutation |- |correct |answer |-A |mutation |that |changes |an |amino |acid |codon |to |one |of |the
|three |stop |codons, |resulting |in |a |shorter |and |usually |nonfunctional |protein.
missense |mutation |- |correct |answer |-A |base-pair |substitution |that |results |in |a |codon |that |codes |for
|a |different |amino |acid.
Deletions/insertions |are |usually |- |correct |answer |-frameshift |mutations
UV |light |causes |the |formation |of |- |correct |answer |-pyrimidine |dimers |which |can |cause |mistakes
|during |DNA |replication
