Genetics Flashcards
(31 cards)
Enzyme that unwinds the
double helix, in a process that
is driven by ATP
Helicase
Enzyme that relieves
torsional strain that results
from helicase-induced
unwinding
Topoisomerases
Type of topoisomerase
inhibited by fluoroquinolones
Topoisomerase type II
(gyrase)
Enzyme that synthesizes
short segments of
complementary RNA primers
Primase
Enzyme that elongates the
DNA strand by adding new
deoxyribonucleotides in the
5’ to 3’ direction
DNA polymerase III
Enzyme that removes the
ribonucleotides using its
5’→3’ exonuclease
DNA polymerase I
Enzyme that seals the nick by
catalyzing the formation of
the last phosphodiester bond,
requiring hydrolysis of ATP
DNA ligase
Refers to the synthesis of
RNA using DNA as a template
Transcription
Steps involved in RNA
synthesis
Initiation → Elongation →
Termination
States that multiple codons
may code for the same amino
acid
Degenerate
States that a specific codon
always codes for the same
amino acid
Unambiguous
States that the codons are
read in a continuing sequence
of nucleotide triplets until a
translation stop codon is
reached
Nonoverlapping
States that the genetic code
has been conserved from
very early stages of evolution
with only slight differences in
the way the code translated
Universal
Steps involved in RNA
synthesis
Initiation → Elongation →
Termination
Point mutation involving
purine to purine or
pyrimidine to pyrimidine
changes
Transition
Point mutation involving
purine to pyrimidine or
pyrimidine to purine changes
Transversion
Point mutation wherein new
codon codes for same amino
acid
Silent mutation
Point mutation wherein new
codon codes for different
amino acid (conservative if
new amino acid is similar in
chemical structure)
Missense mutation
Point mutation wherein new
codon is a stop codon
Nonsense mutation
Type of mutation involving
deletion or addition of bases
that should not be multiples
of three
Frame shift mutation
Type of mutation involving
loss of large areas of
chromosomes during unequal
crossover in meiosis
Large segment deletion
Type of mutation wherein
splice site is lost resulting to
variable effects ranging from
addition or deletion of a few
amino acids to deletion of an
entire exon
Splice donor or acceptor
deletion
Type of mutation wherein
expansions in coding regions
cause protein product to be
longer than normal and
unstable
Triple repeat expansion
Trinucleotide repeat in
patients with Fragile X
syndrome
CGG
