Studied by 2 people
DNA in prokaryotes
is not enclosed in a membranous envelope
DNA in eurkaryotes
Is contained in the nucleus
forms a complex with histones to form chromatin
What is the difference between DNA and RNA?
DNA contains all the genetic content of an organism and controls all cellular activities by turning genes on or off
Sugar is deoxyribose
Double stranded
Bases ATGC
RNA is mostly involved in protein synthesis
Sugar is ribose
Single stranded
Bases AUGC
What composes a nucleotide?
nitrogenous base
pentose sugar (five carbon)
phosphate group
What are the four possible nitrogenous bases in DNA?
(A) Adenine
(G) Guanine
(C) Cytosine
(T) Thymine
Why are ‘nitrogenous bases’ considered bases?
Because they contain and amino group that has the potential of binding an extra hydrogen, and thus decreasing the hydrogen ion concentration in its environment, making it more basic.
What is the difference between purines and pyrimidines?
Purines primary structure is 2 carbon-nitrogen rings
Pyrimidines primary structure is 1 carbon-nitrogen ring
What are the nitrogenous bases in DNA vs. RNA
DNA - ATGC - All The Good Code
RNA - AUGC - All Uther Good Code
Which nitrogenous bases are purines?
(A) Adenine
(G) Guanine
Which nitrogenous bases are pyrimidines?
(C) Cytocine
(T) Thymine
(U) Uracil
Identify the prime connection points of the carbon atoms in
1’
2’
3’
4’
5’ - Phosphate residue attaches
What is a 5’-3’ phosphodiester linkage?
The phosphate residue attaches to the hydroxyl group of the 5’ carbon of one sugar and the hydroxyl group of the 3’ carbon of the sugar of the next nucleotide.
What is antiparallel orientation? Why is it significant?
The two helical strands of DNA run in opposite directions but match the parallel strand so that the 5’ carbon on one faces the 3’ carbon on the other.
Important for replication and nucleic acid interactions.
In DNA, what are the allowable base pairings?
A - T
G - C
Note 
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