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Name:  C. L.
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Are codons universal? For instance, are they assigned to the same amino acids in other organisms like flowers and fish?

Yes. All known living things on earth use the same genetic code.

Richard Barrans Jr., Ph.D.

yes the genetic code is universal. However there are multiple choices per amino acid, and the preferred codon for a given amino acid may differ between organisms. The only exception to the general genetic code is that used by mitochondria. These are small organelles inside a cell that provide the cell with energy and where respiration takes place. These organelles contain their own DNA and here they use a few different codons, eg. TGA (or more correctly UGA) means STOP in the general genetic code, but tryptophane in mammalial mitochondria. There are 4 other codons that differ between mitochondria and the rest of the genetic world.Other than that, we can all read eachothers DNA, between animals, plants, and even bacteria. The meaning of the resulting protein may remain a mistery to us, though.

Dr. Trudy Wassenaar

Absolutely!! This is one of the best pieces of evidence for a common ancestor for all life because all living things use the same genetic code and the proteins made are put together by the same amino acids.

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