Molecular Diagnostics Technologist in Molecular
Biology, MB(ASCP) Exam Study guide Practice
Comprehensive Resource To Help You Ace 2026-2027
Exams Includes Frequently Tested Questions With
ELABORATED 100% Correct COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!! Current Update!!
1. Pyrimidine - Correct Answer: One carbon ring
Cytosine, Thymine, Uracil
2. Purine - Correct Answer: Two carbon rings
Adenine, Guanine
3. How are nucleotides joined together? - Correct Answer: Condensation
to form phosphodiester bond
4. What is the function of mRNA? - Correct Answer: Carries genetic info
out of nucleus
Transcript translated to protein
5. What is the function of tRNA? - Correct Answer: Carries aa to ribosome
Anticodon pairs with codon on mRNA strand
,6. What is the function of rRNA? - Correct Answer: part of ribosome
structure
most abundant RNA
coordinated coupling of tRNA to mRNA codons
7. Feedback inhibition - Correct Answer: Product of pathway is
noncompetitive inhibitor
Binds to allosteric site to slow down rxn b/c too much product
8. 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'
9. Endonucleases (Prok) - Correct Answer: Restriction enzymes
Cleaves phoshpodiester bonds w/i poly-nt chain
Recognition site is palindromic sequence
Types I-V
10.ORI sites - Correct Answer: nt sequence where replication is initiated
11.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
,12.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
13.Gyrase (topoisomerase II) - Correct Answer: Unwinds supercoiling
caused by unwinding at the rep fork by introducing DSBs
14.Helicase - Correct Answer: Breaks H-bonds of double helix at the
replication fork
15.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
16.single-strand DNA binding proteins (SSBPs) - Correct Answer: Binds
ssDNA and prevents it from re-annealing during TXN, replication, repair, and
recombination
17.Okazaki fragments - Correct Answer: Short fragments of DNA
synthesized by DNApol δ using the lagging strand (3'->5') as a template
18.Ligase - Correct Answer: Closes gaps in DNA
Catalyzes phosphodiester bond between 3'OH and 5'P
19.What are the steps in DNA replication? - Correct Answer: 1. Initiate
2. Elongate
, 3. Terminate
20.Telomeres - Correct Answer: Repeat sequence (TTAGGG) at the ends of
chr, protect chr from degradation
21.RNA polymerase - Correct Answer: DNA dependent RNApol
Transcribes DNA template to RNA (3'-->5'; anti-parallel)
22.Splicesomes - Correct Answer: Complex of snRNPs
Removes introns from pre-mRNA and splices exons together
23.Enhancers - Correct Answer: Short regions of DNA that bind proteins
(TXN factors) that enhance TXN of a gene
24.Poly-A tail - Correct Answer: Prevents mRNA from being degraded in
cytoplasm
100-250 A's at 3' end
25.5' 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
26.aminoacyl tRNA - Correct Answer: tRNAs that carry amino acids
27.Ribosomes - Correct Answer: Where TLN occurs
Biology, MB(ASCP) Exam Study guide Practice
Comprehensive Resource To Help You Ace 2026-2027
Exams Includes Frequently Tested Questions With
ELABORATED 100% Correct COMPLETE SOLUTIONS
Guaranteed Pass First Attempt!! Current Update!!
1. Pyrimidine - Correct Answer: One carbon ring
Cytosine, Thymine, Uracil
2. Purine - Correct Answer: Two carbon rings
Adenine, Guanine
3. How are nucleotides joined together? - Correct Answer: Condensation
to form phosphodiester bond
4. What is the function of mRNA? - Correct Answer: Carries genetic info
out of nucleus
Transcript translated to protein
5. What is the function of tRNA? - Correct Answer: Carries aa to ribosome
Anticodon pairs with codon on mRNA strand
,6. What is the function of rRNA? - Correct Answer: part of ribosome
structure
most abundant RNA
coordinated coupling of tRNA to mRNA codons
7. Feedback inhibition - Correct Answer: Product of pathway is
noncompetitive inhibitor
Binds to allosteric site to slow down rxn b/c too much product
8. 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'
9. Endonucleases (Prok) - Correct Answer: Restriction enzymes
Cleaves phoshpodiester bonds w/i poly-nt chain
Recognition site is palindromic sequence
Types I-V
10.ORI sites - Correct Answer: nt sequence where replication is initiated
11.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
,12.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
13.Gyrase (topoisomerase II) - Correct Answer: Unwinds supercoiling
caused by unwinding at the rep fork by introducing DSBs
14.Helicase - Correct Answer: Breaks H-bonds of double helix at the
replication fork
15.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
16.single-strand DNA binding proteins (SSBPs) - Correct Answer: Binds
ssDNA and prevents it from re-annealing during TXN, replication, repair, and
recombination
17.Okazaki fragments - Correct Answer: Short fragments of DNA
synthesized by DNApol δ using the lagging strand (3'->5') as a template
18.Ligase - Correct Answer: Closes gaps in DNA
Catalyzes phosphodiester bond between 3'OH and 5'P
19.What are the steps in DNA replication? - Correct Answer: 1. Initiate
2. Elongate
, 3. Terminate
20.Telomeres - Correct Answer: Repeat sequence (TTAGGG) at the ends of
chr, protect chr from degradation
21.RNA polymerase - Correct Answer: DNA dependent RNApol
Transcribes DNA template to RNA (3'-->5'; anti-parallel)
22.Splicesomes - Correct Answer: Complex of snRNPs
Removes introns from pre-mRNA and splices exons together
23.Enhancers - Correct Answer: Short regions of DNA that bind proteins
(TXN factors) that enhance TXN of a gene
24.Poly-A tail - Correct Answer: Prevents mRNA from being degraded in
cytoplasm
100-250 A's at 3' end
25.5' 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
26.aminoacyl tRNA - Correct Answer: tRNAs that carry amino acids
27.Ribosomes - Correct Answer: Where TLN occurs
