A.1.2: Nucleic Acids

Nucleotide components

Nucleotide components

Phosphate group, pentose sugar, organic base

How does the phosphate group bind to the sugar?

Covalent bond: oxygen in phosphate binds to carbon in sugar

Condensation reaction

Joining two nucleotides

Hydrolysis

Breaking apart two nucleotides

How do organic bases in the double helix bond?

Hydrogen bond, creates the double helix

Key differences between DNA and RNA

• Ribose instead of deoxyribose

• Single-strand rather than double

• Uracil instead of Thymine as an organic base

What is the difference between ribose and deoxyribose?

Ribose has 1 more oxygen molecule

mRNA

Transports genetic coding information out of the nucleus and presents it to synthesise a protein

tRNA

Transfers the correct amino acids into an ongoing chain to synthesise a specific protein

rRNA

Creates ribosomes

Triplet codon

Three-base sequence coding for amino acids

Stop-codon

UAA, UAG, UGA

5’ (prime) end

Beginning end of a single DNA or RNA strand, unbound phosphate

3’ (prime) end

End of a single DNA or RNA strand, unbound pentose sugar

Percentage difference in DNA between humans

1%