ASCP Molecular Biology Certification
Exam Questions With Correct Answers
Pyrimidine |- |CORRECT |ANSWER✔✔-One |carbon |ring
Cytosine, |Thymine, |Uracil
Purine |- |CORRECT |ANSWER✔✔-Two |carbon |rings
Adenine, |Guanine
How |are |nucleotides |joined |together? |- |CORRECT |ANSWER✔✔-Condensation |to |form |
phosphodiester |bond
What |is |the |function |of |mRNA? |- |CORRECT |ANSWER✔✔-Carries |genetic |info |out |of |nucleus
Transcript |translated |to |protein
What |is |the |function |of |tRNA? |- |CORRECT |ANSWER✔✔-Carries |aa |to |ribosome
Anticodon |pairs |with |codon |on |mRNA |strand
What |is |the |function |of |rRNA? |- |CORRECT |ANSWER✔✔-part |of |ribosome |structure
most |abundant |RNA
coordinated |coupling |of |tRNA |to |mRNA |codons
Feedback |inhibition |- |CORRECT |ANSWER✔✔-Product |of |pathway |is |noncompetitive |inhibitor
Binds |to |allosteric |site |to |slow |down |rxn |b/c |too |much |product
,Exonucleases |- |CORRECT |ANSWER✔✔-Degrades |nucleic |acids |by |removing |one |terminal |nt |at |
a |time
Cleaves |phosphodiester |bond |at |end |of |chain
5' |--> |3' |and |3' |--> |5'
Endonucleases |(Prok) |- |CORRECT |ANSWER✔✔-Restriction |enzymes
Cleaves |phoshpodiester |bonds |w/i |poly-nt |chain
Recognition |site |is |palindromic |sequence
Types |I-V
ORI |sites |- |CORRECT |ANSWER✔✔-nt |sequence |where |replication |is |initiated
Topoisomerase |I |- |CORRECT |ANSWER✔✔-Induces |ss |breaks
Remove |DNA |supercoils |during |TXN |and |DNA |replication; |for |strand |breakage |during |
recombination; |for |chr |condensation; |and |to |disentangle |intertwined |DNA |during |mitosis
topoisomerase |II |- |CORRECT |ANSWER✔✔-cuts |both |strands |of |one |DNA |double |helix, |passes |
another |unbroken |DNA |helix |through |it, |and |then |reanneals |the |cut |strands
Gyrase |(topoisomerase |II) |- |CORRECT |ANSWER✔✔-Unwinds |supercoiling |caused |by |unwinding |
at |the |rep |fork |by |introducing |DSBs
Helicase |- |CORRECT |ANSWER✔✔-Breaks |H-bonds |of |double |helix |at |the |replication |fork
Primase |- |CORRECT |ANSWER✔✔-DNApol |α |(DNA |dep |RNA |pol)
adds |short |segments |of |complementary |
RNA |to |ssDNA |template |(primers), |serves |as |starting |points |for |replication
,single-strand |DNA |binding |proteins |(SSBPs) |- |CORRECT |ANSWER✔✔-Binds |ssDNA |and |prevents
|it |from |re-annealing |during |TXN, |replication, |repair, |and |recombination
Okazaki |fragments |- |CORRECT |ANSWER✔✔-Short |fragments |of |DNA |synthesized |by |DNApol |δ |
using |the |lagging |strand |(3'->5') |as |a |template
Ligase |- |CORRECT |ANSWER✔✔-Closes |gaps |in |DNA |
Catalyzes |phosphodiester |bond |between |3'OH |and |5'P
What |are |the |steps |in |DNA |replication? |- |CORRECT |ANSWER✔✔-1. |Initiate
2. |Elongate
3. |Terminate
Telomeres |- |CORRECT |ANSWER✔✔-Repeat |sequence |(TTAGGG) |at |the |ends |of |chr, |protect |chr |
from |degradation
RNA |polymerase |- |CORRECT |ANSWER✔✔-DNA |dependent |RNApol
Transcribes |DNA |template |to |RNA |(3'-->5'; |anti-parallel)
Splicesomes |- |CORRECT |ANSWER✔✔-Complex |of |snRNPs
Removes |introns |from |pre-mRNA |and |splices |exons |together
Enhancers |- |CORRECT |ANSWER✔✔-Short |regions |of |DNA |that |bind |proteins |(TXN |factors) |that |
enhance |TXN |of |a |gene
Poly-A |tail |- |CORRECT |ANSWER✔✔-Prevents |mRNA |from |being |degraded |in |cytoplasm
, 100-250 |A's |at |3' |end
5' |cap |- |CORRECT |ANSWER✔✔-5'-5' |pyrophosphate |bridge |to |a |methylated |G |added |to |5' |end |
of |a |mRNA
Protects |against |degradation |and |as |a |recognition |signal |for |TLN |apparatus
aminoacyl |tRNA |- |CORRECT |ANSWER✔✔-tRNAs |that |carry |amino |acids
Ribosomes |- |CORRECT |ANSWER✔✔-Where |TLN |occurs
Prok: |30s |and |50s
Euk: |40s |and |60s
Catalyzes |peptide |bond |between |a.a.'s
What |is |the |path |of |a |tRNA |in |a |ribosome? |- |CORRECT |ANSWER✔✔-Acceptor |> |Peptidyl |> |Exit
How |is |translation |initiated? |- |CORRECT |ANSWER✔✔-small |rRNA |(40S) |subunit |binds |mRNA |
and |scans |for |start |codon |(AUG)
Met-tRNA |is |brought |to |the |P |site
Large |rRNA |(60S) |subunit |binds
How |is |translation |terminated? |- |CORRECT |ANSWER✔✔-Occurs |when |stop |codon |enters |A |site
Release |factor |recognizes |stop |codon, |hydrolyzes |ester |bond |with |P |site, |releasing |aa |chain
Reverse |transcriptase |- |CORRECT |ANSWER✔✔-enzyme |that |transcribes |RNA |to |cDNA |(lacks |
introns)
RNA |--> |RNA:DNA |--> |cDNA |(dsDNA)
Exam Questions With Correct Answers
Pyrimidine |- |CORRECT |ANSWER✔✔-One |carbon |ring
Cytosine, |Thymine, |Uracil
Purine |- |CORRECT |ANSWER✔✔-Two |carbon |rings
Adenine, |Guanine
How |are |nucleotides |joined |together? |- |CORRECT |ANSWER✔✔-Condensation |to |form |
phosphodiester |bond
What |is |the |function |of |mRNA? |- |CORRECT |ANSWER✔✔-Carries |genetic |info |out |of |nucleus
Transcript |translated |to |protein
What |is |the |function |of |tRNA? |- |CORRECT |ANSWER✔✔-Carries |aa |to |ribosome
Anticodon |pairs |with |codon |on |mRNA |strand
What |is |the |function |of |rRNA? |- |CORRECT |ANSWER✔✔-part |of |ribosome |structure
most |abundant |RNA
coordinated |coupling |of |tRNA |to |mRNA |codons
Feedback |inhibition |- |CORRECT |ANSWER✔✔-Product |of |pathway |is |noncompetitive |inhibitor
Binds |to |allosteric |site |to |slow |down |rxn |b/c |too |much |product
,Exonucleases |- |CORRECT |ANSWER✔✔-Degrades |nucleic |acids |by |removing |one |terminal |nt |at |
a |time
Cleaves |phosphodiester |bond |at |end |of |chain
5' |--> |3' |and |3' |--> |5'
Endonucleases |(Prok) |- |CORRECT |ANSWER✔✔-Restriction |enzymes
Cleaves |phoshpodiester |bonds |w/i |poly-nt |chain
Recognition |site |is |palindromic |sequence
Types |I-V
ORI |sites |- |CORRECT |ANSWER✔✔-nt |sequence |where |replication |is |initiated
Topoisomerase |I |- |CORRECT |ANSWER✔✔-Induces |ss |breaks
Remove |DNA |supercoils |during |TXN |and |DNA |replication; |for |strand |breakage |during |
recombination; |for |chr |condensation; |and |to |disentangle |intertwined |DNA |during |mitosis
topoisomerase |II |- |CORRECT |ANSWER✔✔-cuts |both |strands |of |one |DNA |double |helix, |passes |
another |unbroken |DNA |helix |through |it, |and |then |reanneals |the |cut |strands
Gyrase |(topoisomerase |II) |- |CORRECT |ANSWER✔✔-Unwinds |supercoiling |caused |by |unwinding |
at |the |rep |fork |by |introducing |DSBs
Helicase |- |CORRECT |ANSWER✔✔-Breaks |H-bonds |of |double |helix |at |the |replication |fork
Primase |- |CORRECT |ANSWER✔✔-DNApol |α |(DNA |dep |RNA |pol)
adds |short |segments |of |complementary |
RNA |to |ssDNA |template |(primers), |serves |as |starting |points |for |replication
,single-strand |DNA |binding |proteins |(SSBPs) |- |CORRECT |ANSWER✔✔-Binds |ssDNA |and |prevents
|it |from |re-annealing |during |TXN, |replication, |repair, |and |recombination
Okazaki |fragments |- |CORRECT |ANSWER✔✔-Short |fragments |of |DNA |synthesized |by |DNApol |δ |
using |the |lagging |strand |(3'->5') |as |a |template
Ligase |- |CORRECT |ANSWER✔✔-Closes |gaps |in |DNA |
Catalyzes |phosphodiester |bond |between |3'OH |and |5'P
What |are |the |steps |in |DNA |replication? |- |CORRECT |ANSWER✔✔-1. |Initiate
2. |Elongate
3. |Terminate
Telomeres |- |CORRECT |ANSWER✔✔-Repeat |sequence |(TTAGGG) |at |the |ends |of |chr, |protect |chr |
from |degradation
RNA |polymerase |- |CORRECT |ANSWER✔✔-DNA |dependent |RNApol
Transcribes |DNA |template |to |RNA |(3'-->5'; |anti-parallel)
Splicesomes |- |CORRECT |ANSWER✔✔-Complex |of |snRNPs
Removes |introns |from |pre-mRNA |and |splices |exons |together
Enhancers |- |CORRECT |ANSWER✔✔-Short |regions |of |DNA |that |bind |proteins |(TXN |factors) |that |
enhance |TXN |of |a |gene
Poly-A |tail |- |CORRECT |ANSWER✔✔-Prevents |mRNA |from |being |degraded |in |cytoplasm
, 100-250 |A's |at |3' |end
5' |cap |- |CORRECT |ANSWER✔✔-5'-5' |pyrophosphate |bridge |to |a |methylated |G |added |to |5' |end |
of |a |mRNA
Protects |against |degradation |and |as |a |recognition |signal |for |TLN |apparatus
aminoacyl |tRNA |- |CORRECT |ANSWER✔✔-tRNAs |that |carry |amino |acids
Ribosomes |- |CORRECT |ANSWER✔✔-Where |TLN |occurs
Prok: |30s |and |50s
Euk: |40s |and |60s
Catalyzes |peptide |bond |between |a.a.'s
What |is |the |path |of |a |tRNA |in |a |ribosome? |- |CORRECT |ANSWER✔✔-Acceptor |> |Peptidyl |> |Exit
How |is |translation |initiated? |- |CORRECT |ANSWER✔✔-small |rRNA |(40S) |subunit |binds |mRNA |
and |scans |for |start |codon |(AUG)
Met-tRNA |is |brought |to |the |P |site
Large |rRNA |(60S) |subunit |binds
How |is |translation |terminated? |- |CORRECT |ANSWER✔✔-Occurs |when |stop |codon |enters |A |site
Release |factor |recognizes |stop |codon, |hydrolyzes |ester |bond |with |P |site, |releasing |aa |chain
Reverse |transcriptase |- |CORRECT |ANSWER✔✔-enzyme |that |transcribes |RNA |to |cDNA |(lacks |
introns)
RNA |--> |RNA:DNA |--> |cDNA |(dsDNA)
