DNA Flashcards
What are the repeating units of DNA
dNMP
What type of linkage connects each nucleotide within a chain.
phosphodiester linkage
What type of bond connects the bases of the two antiparallel chains?
hydrogen bonds
T/F In a living cell, 99% of the DNA is found in the B-DNA conformation.
True
Remember this about B-DNA
- a right-handed helix.
- base pairs per turn of the helix.
- base pairs lying flat and perpendicular to the axis.
- a propeller twist
- base pairs exposed in the major and minor grooves.
What is the conformation of dehydrated DNA?
A-DNA
Which type of DNA makes about 1% of cellular DNA, is found in regions of high C-G concentration and has a left-handed helix.
Z-DNA
Separating two DNA strands is referred to as
denature
Complementary single strands of DNA anneal to each other by base pairing.
anneal
A unit of heredity is referred to as
gene
The complete set of genetic material present in a cell or organism
genome
contains a DNA molecule that encodes genes
chromosomes
T/F DNA polymerase adds one dNMP to the 5’ end of a growing DNA chain.
False. 3’
T/F DNA polymerases require a DNA template chain and but not a primer.
False
T/F RNA polymerases require a DNA template chain but not a primer.
True
T/F DNA polymerase adds one NMP to the 3’ end of the growing chain.
False. dNMP
T/F RNA polymerase adds one NMP to the 3’ end of the growing chain
True
T/F Reverse transcriptases require an DNA template chain and a primer.
False. RNA template
T/F Nucleases synthesize polynucleotide chains whereas polymerases digest polynucleotide chains.
False. The reverse
___________ breaks a phosphodiester bond within a polynucleotide chain.
Endonuclease
____________ breaks two phosphodiester bonds within a single polynucleotide chain.
Excinuclease
_____________ removes nucleotides from one end of a polynucleotide chain.
Exonuclease
links two existing DNA chains together end-to-end by catalyzing formation of phosphodiester bond.
DNA ligase
T/F An exonuclease is can be either a DNase or an RNase.
True
T/F Exonucleases are specific for digesting a polynucleotide from the 5’ to 3’ end.
False. It can be from either end
T/F Endonuclease are molecule-specific but exonucleases are not.
True
Which type of hypothesis yields an original intact DNA molecule and one entirely newly synthesized DNA
conservative replication
Which hypothesis yields two DNA molecules, each with one parental and one newly synthesized strand.
semi-conservative replication
Which hypothesis yields two DNA molecules that are hybrids (or mixtures) of parental and newly synthesized DNA.
dispersive replication
The catalytic site for DNA synthesis is located in the “_________” of the enzyme.
palm
T/F G-U base pairing is allowed when DNA base pairs with itself or another RNA molecule.
False. It’s RNA
