ASCP MOLECULAR BIOLOGY CERTIFICATION EXAM
LATEST VERSION WITH VERIFIED ANSWERS/A+ GRADE
Pyrimidine - Answer One carbon ring
Cytosine, Thymine,
... [Show More] Uracil
Purine - Answer Two carbon rings
Adenine, Guanine
How are nucleotides joined together? - Answer Condensation to form phosphodiester
bond
What is the function of mRNA? - Answer Carries genetic info out of nucleus
Transcript translated to protein
What is the function of tRNA? - Answer Carries aa to ribosome
Anticodon pairs with codon on mRNA strand
What is the function of rRNA? - Answer part of ribosome structure
most abundant RNA
coordinated coupling of tRNA to mRNA codons
Feedback inhibition - Answer Product of pathway is noncompetitive inhibitor
Binds to allosteric site to slow down rxn b/c too much product
Exonucleases - 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) - Answer Restriction enzymes
Cleaves phoshpodiester bonds w/i poly-nt chain
Recognition site is palindromic sequence
Types I-V
ORI sites - Answer nt sequence where replication is initiated
Topoisomerase I - 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 - 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) - Answer Unwinds supercoiling caused by unwinding at the
rep fork by introducing DSBs
ASCP MOLECULAR BIOLOGY CERTIFICATION EXAM
LATEST VERSION WITH VERIFIED ANSWERS/A+ GRADE
Helicase - Answer Breaks H-bonds of double helix at the replication fork
Primase - 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) - Answer Binds ssDNA and prevents it
from re-annealing during TXN, replication, repair, and recombination
Okazaki fragments - Answer Short fragments of DNA synthesized by DNApol δ using
the lagging strand (3'->5') as a template
Ligase - Answer Closes gaps in DNA
Catalyzes phosphodiester bond between 3'OH [Show Less]