DNA - Genetic Code

Genetic Code
1. Characteristics
  1. It is a triplet code - 4 to the power of 3 = 64 - only twenty amino acids used for protein synthesis
  2. It is a degenerate code (all amino acids have more the one code) apart from methionine.
  3. stop and start codons
  4. wide spread but not universal
Transcription
1. 1) The gene to be transcribed, unwinds and unzips by dipping into the nucleus, hydrogen bonds between base pairs break
  1. 2) activated RNA nucleotides hydrogen bonds to the exposed complementary base pairs - catalysed by RNA polymerase
    1. 3) The two extra phosphates are released, providing energy for bonding of adjacent molecules
      1. 4) The mRNA produced is complementary to the template strand and is therefore a copy of the coding strand of DNA.
        5) The mRNA is released from the DNA and passed out of the nuclear pore to a ribosome
2. Is the creating of a single-stranded mRNA copy of the DNA coding strand
Genome
1. The genome of an organism is the entire DNA sequence of that organism, the human genome consists of about 3 billion nucleotide base pairs

Resource summary

	Created by aaron.mackenzie over 9 years ago