How is it possible that an mRNA can have 15 different codons, but only 10 different amino Acids?

Answer 1

For humans there are actually 64 codons. Each codon is three bases long, and there are four options for each base. 4 x 4 x 4 = 64.

Likewise, humans have 20 amino acids, plus there are 'start' and 'stop' codons. So that's 22 different things that are coded for.

Still, your point is still valid - 64 things are coding for only 22 things. The obvious answer is that sometimes different codes have the same outcome.

It is not, however, evenly divided! There is only one code for 'start' or methionine, for example, but leucine and serine each of six codes! I'm sure some of it has to do with relative importance and availability of the difference amino acids... and some of it is probably just slightly random too.

So it goes. Hope that helps!

Answer 2

Since there are 20 different amino acids; and these amino acids are used to make proteins, how does the information get from the DNA to the final protein product? In a DNA molecule the only variable part is the 4 different bases. How can 4 bases, or combinations there of , code for the 20 different amino acids?

1. If 1 base coded for 1 amino acid = 41 (4) amino acids coded for.

2. If 2 bases coded for 1 amino acid = 42 (16) amino acids coded for.

3. If 3 bases coded for 1 amino acid = 43 ( 64) amino acids coded for.

Notice the large gap between 2 and 3. It was concluded that each coding part of DNA (codon) consisted of 3 bases. Since 64 is larger than the 20 amino acids, it stands to reason that some amino acids are coded for by different codons.

Answer 3

1. B 2. A 3. A 4. B 5. A 6. B 7. B 8. C 9. C 10. B 11. B 12. B 13. B 14. A 15. A 16. A 17. A 18. B 19. C 20. A

Answer 4

Because some codons code for the same amino acid. Arginine, for example, has several different codons that code for it. This is our body's way of protecting itself against point mutations.

Answer 5

All the amino acids can be put together using more than one codon.

Please check this out:

http://en.wikipedia.org/wiki/Genetic_code

Answer 6

redundancy of the genetic code