Structure of DNA and RNA Flashcards
1
Q
Who discovered DNA and when?
A
Watson and Crick in 1953
2
Q
What are the main features of DNA structure?
A
- Double stranded (2 polynucleotide strands)
- Strands and anti parallel (run in opposite directions)
- Double helix (polynucleotide strands wound around eachother)
3
Q
What is the double helix joined with?
A
- Hydrogen bonds
- Between complEmentary base pairs (A+T, G+C)
4
Q
How many carbons are there in a pentose sugar?
A
5
5
Q
What does carbon 5 join to?
A
Phosphate
6
Q
What does carbon 3 join to?
A
The next nucleotide via its phosphate
7
Q
What kind of base is C+T
A
Pyrimidine base (single ring)
8
Q
What kind of base is A+G
A
Purine base (double ring)
9
Q
How many hydrogen bonds are there between A+T
A
2
10
Q
How many hydrogen bonds are there between C+G
A
3
11
Q
What is the use of the complementary strands?
A
There are two copies of the information for repair, copying and error checking
12
Q
What does the amount of hydrogen bonds mean?
A
That DNA is very stable and not easily damaged
13
Q
What are the differences between DNA and RNA
A
- RNA is made of ribose nucleotides
- RNA has the base Uracil (U) instead of Thymine (T)
- RNA is single stranded
- RNA is shorter than DNA
14
Q
A
