Nucleotides
Biology: AQA A Level, topic 1.5.2
Nucleic Acids
Nucleic acids carry the cell's genetic code. These are the instructions for the function of the cell. Nucleic acids are important for passing on information from generation to generation.
Components of nucleic acids
- DNA and RNA are made of monomers called nucleotides.
- Nucleotides join together to form polynucleotides.
- Polynucleotides make up nucleic acids such as DNA or RNA.
Structure of nucleotides
- Each nucleotide is formed from a pentose sugar, a nitrogen-containing organic base and a phosphate group.
- A condensation reaction between two nucleotides forms a phosphodiester bond.
- These condensation reactions happen between a sugar group on one nucleotide and a phosphate group on a different nucleotide.
DNA nucleotide
- The components of a DNA nucleotide are:
- A deoxyribose sugar.
- A phosphate group.
- An organic base - adenine (A), cytosine (C), guanine (G), thymine (T).
- The components of an RNA nucleotide are:
- A ribose sugar.
- A phosphate group.
- An organic base - adenine (A), cytosine (C), guanine (G), uracil (U).
Test yourself on Nucleotides
Which of the following is an example of a nucleic acid?
Which of the following organic bases are found in DNA nucleotides but NOT in RNA nucleotides?