DNA by C. Stephen Murray. All life stores its genetic code in a molecule called DNA.
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DNA by C. Stephen Murray
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Transcript of DNA by C. Stephen Murray. All life stores its genetic code in a molecule called DNA.
Many make a double helix, if you add another side.
Sugar phosphate backbone (side)
Nitrogen base pairs
Nitrogen base
It’s in the sequence of the nitrogen bases that together form our genes.
ATTCGATCGGACT
Nitrogen base sequence
Genes form chromosomes
When it makes a mistake when it replicates this is when DNA can mutate.
Original – ATTCGATCGGACT
Mutation - ATTGATCGGACT
“C” was deleted
Original – ATTCGATCGGACT
Mutation - ATTCGATACGGACT
“A” was inserted
But if it doesn’t pass to the offspring it doesn’t really matter at all.
DNA
Mutation to ribosomes
No problem
Mutation to egg or sperm
Passes to offspring
When it replicates each nitrogen base always has to pair in a certain way.
Original1 DNA
Replicas2 DNAs