DNA Structure Flashcards
What makes up a nucleotide?
- Nitrogenous base
- Pentose Sugar
- One or more phosphate groups
What is a nucleoside?
Nitrogenous base+sugar (w/o phosphate group)
Where does the phosphate attach to the sugar?
5’C
Where does the nitrogenous base attach to the sugar?
1’C
What are the two groups of nitrogenous bases? Describe each and what makes up each group.
Pyrimidines- single ring C, T
Purines- double-ringed A, G
What is deoxyribose and what does it correspond with?
Missing one O bonded to 2’C (in DNA)
What is ribose and what does it correspond with?
Has OH bonded to 2’C
What reaction makes polynucleotides?
Dehydration reaction
Where does the phosphodiester linkage occur?
Sugar-phosphate backbone
What side of the polynucleotide do you add to?
3’ side
What is Rosalind Franklin known for?
Proposed 2 strands with sugar-phosphate backbone and bases on the interior after using X-ray Crystallography
What is Watson and Crick known for?
Build models of a double helix to conform to the X-rays and chemistry of DNA
What is the shape of DNA?
Double helix
What does it mean to be antiparallel in structure?
Backbone runs opposite 5’->3’
What bond links base pairs?
H-bonding
What is the pairing of the base pairs?
A-T and C-G
What is right handed chirality?
Twist moves helix away
What is the helical pitch?
The height of one full turn which consists of 10 base pairs
How many h-bonds are in A-T bonding?
2
How many h-bonds are in C-G bonding?
3
What does more h-bonds mean?
More stable
The 5’ side of DNA will match with what?
3’ side of complementing pair
What kind of structure does RNA have?
Single stranded
What are the different types of RNA?
mRNA, tRNA, rRNA, sRNA