Nucleic Acids Flashcards
(28 cards)
What are nucleotides?
Linear, unbranched polymers that have repeating monomer units
Where are nucleic acids found within the body?
Everywhere but red blood cells
What is the molecular weight of nucleic acids?
25000 to over 50 billion amu
What is the monomer unit for nucleic acids?
Nucleotides
Nucleotides are composed of what three parts?
A five carbon sugar, a phosphate group, and a nitrogen base.
A five carbon sugar and a nitrogen base combined are called what?
A nucleoside
Where do the pentose molecules attach to their phosphate group, nitrogen base and the phosphate group of the nucleotide above
5’
1’
3’
Phosphates are bonded how?
Polar covalently
Where do phosphates bond to their pentose, of the pentose above
5’
3’
How many phosphate groups can a nucleotide have?
Up to 3(tri)
ATP stands for what?
Adenosine triphosphate
What makes up a DNA backbone?
Pentoses and phosphate groups
What makes up the rungs of the DNA ladder?
Nitrogen bases
Purines are nitrogen bases with how many rings?
Two. Examples are adenine and guanine.
Pyrimidines are nitrogen bases with how many rings?
One ring. Examples are thymine, cytosine, uracil.
DNA is read by…
enzymes from 5’ to 3’
James Watson and Francis Crick discovered what?
How nucleotides were arranged (1963)
Rosalind Franklin discovered what?
Used x-ray crystallographer to find that the DNA molecule was a helix coil with a diameter of 2nm and made a complete spiral every 3.4 nm
What did Erwin chargaff discover?
That the number of guanine units equals the number of cytosine units and the number of adenine units equals the number of thymine units. (Chargaffs rule)
How many chromosomes do humans have?
46
How many hydrogen bonds hold each pair of nitrogenous bases together
AT=2
CG=3 (first pairing from evolution)
DNA exists in what medium?
Nucleoplasm
What is a gene?
A section of DNA located on chromatin that codes for specific proteins. (Exon)
The region before the gene is called what?
A promoter
