Nucleic Acids Flashcards
Central Dogma of Molecular Biology
_____ stores information which is transcribed to make _____.
_____ is then used as a template for translation into a protein.
DNA, RNA, RNA.
Adenine and Guanine (Purines) are composed of ____ ring(s).
2
Cytosine, Uracil, & Thymine (Pyrimidines - spells CUT) are composed of ____ ring(s).
1
These nucleotides, _____ & _______ are used as an energy source for many reactions.
ATP & GTP
The Primary Carbon (1’) is linked to a base via a ______ bond.
Glycosidic
Carbon 2 (2’) have a hydroxyl group attached in _____ and no oxygen attached in ______.
RNA, DNA
Carbon 3 (3’) requires a _______ group in both DNA & RNA so that it may be attached to the 5’ carbon via a _____________ bond.
Hydroxyl, phosphodiester
Carbon 5 (5’) is linked to one or more _________ and joined to Carbon____ through a phosphodiester bond.
Phosphates, 3
DNA is a polar/non-polar molecule with a free 5’ end with a phosphate/hydroxyl group and a free 3’ end with a phosphate/hydroxyl group attached.
”/” say “or”
Polar, Phosphate, Hydroxyl
Nucleotides in DNA are joined by ______ bonds.
Bases are linked by _______ bonds.
Phosphodiester, glycosidic
By convention, if no end designation is made, DNA is assumed to be written in the _____prime to _____prime direction.
5’ to 3’
DNA structure is complementary and anti parallel which means A always pairs with _____ and G always pairs with _____ (via _____ bonds).
T, C, hydrogen
A::T Base Pairing has _____H bonds
2
G::C Base Pairing has ___H bonds
3
DNA is a twisted double helix and is amphipathic. The Hydrogen-bonded base pairs are _______ and form the “stairs” of the helix. The sugar-phosphate backbone is on the outside of the helix and is ________.
Hydrophobic, Hydrophilic
Normally, DNA is a _____-handed helix called a Watson-Crick or B-DNA.
Right
Rarer form of left-handed DNA is called ____-DNA
Function unknown, possibly important for gene expression
Z-DNA
Denaturation of DNA results in _______-stranded DNA.
Single (ssDNA)
G::C bonds have ____ hydrogen bonds and therefore have a ________ Tm (Melting Temp).
3H bonds, Higher
Supercoiling in Prokaryotes and Mitochondrial DNA is accomplished via ______.
(Answer above) is inhibited by __________.
DNA Gyrase (Topoisomerase II)
Inhibited by quinolones
DNA in the nucleus of eukaryotes associates with histone & non-histone proteins forming __________.
________ are packaged tightly to form _________.
Nucleosomes, Nucleosomes, Chromatin
Histones are rich in _________ & ________ (+ charged amino acids).
Lysine and Arginine
Histones are _____ charged and bind strongly to ______ charged DNA.
Positively, negatively
Two units of each histone:
- _____
- _____
- ______
- ________
Aggregate to form the histone ______.
H2A, H2B, H3, H4
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