2.1 Structure of RNA and DNA

DNA (deoxyribonucleic acid) stores genetic information
RNA (ribonucleic acid) transfers genetic information from DNA to the ribosomes
1. Ribosomes formed from RNA and proteins
Nucleotide Structure
1. RNA
  1. Ribose sugar
  2. Phosphate group
  3. 1 of 4 different bases
    1. Cytosine
    2. Guanine
    3. Adenine
    4. Uracil
2. DNA
  1. Pentose sugar
  2. Phosphate group
  3. 1 of 4 different bases
    1. cytosine
    2. Guanine
    3. Adenine
    4. Thymine
Nucleotides Join together to form Polynucleotides
1. A dinucleotide is formed in a condensation reaction between the sugar of one mononucleotide, and the phosphate group of another. The bond between them is a PHOSPHODIESTER bond
2. Chain of sugars and phosphates = sugar-phosphate backbone
DNA Structure
1. 2 DNA polynucleotide stands join together by hydrogen bonding between the bases
  1. 2 H bonds between Adenine and Thymine
  2. 3 H bonds between Cytosine and Guanine
2. Each base only joins with one partner - complementary base pairing
  1. Adenine and Thymine
  2. Cytosine and Guanine
3. Two antiparallel polynucleotide strands twist to form double helix
RNA structure
1. single polynucleotide chain
2. shorter than most DNA polynucleotides

Resource summary

	Created by Bee Brittain over 8 years ago