Transcription and Translation

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Transcription and Translation

• How DNA is used

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Where is DNA?

• Human Cells contain DNA molecules in bundles
  called chromosomes.
• There are 46 chromosomes in each human cell.
  (Except Sex Cells)
• Each molecule is coiled up and bundled much like
  yarn from a craft store.

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• When unwound, DNA looks like a ladder.
• The code of DNA is stored in the sequence of
  bases that make up the rungs to the ladder.

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Transcription

• DNA must remain in the nucleus, but proteins are
  made in the ribosomes.
• The code must be copied through a process called
  transcription.

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• DNA unwinds, and separates to expose 1 side of
  the code.
• mRNA is built by connecting nucleotides 1 at a
  time that are complimentary to the code.
• RNA replaces (T)hymine with (U)racil so it can
  leave the nucleus.

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Translation

• mRNA takes the codons to the ribosome.
• tRNA brings amino acids one at a time in a
  specific order by matching 3 base pairs with the
  mRNA.
• Each new amino acid brought by the tRNAs is added
  to the growing protein chain.

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