Lec 13 MIT 7.014 Introductory Biology, Spring 2005
Julia just mentioned that a few of you had commented, when we were talking about the genetic code, that some of you thought the fact that it was degenerate, it had some redundancy in it, like multiple codons or threonine, that that was kind of cool, and some of you thought it was sort of a waste and would have maybe designed the thing differently. That's, you know, part of when you study biology you don't get to design it from first principles. You found out what happened during evolution and what got selected for. And once it gets selected for then that gets sort of fixed in nature. If there were four nucleotides then you could have one, two and three-letter words. And it's going to be a three-letter word to have at least 20 then you've got some degeneracy or redundancy, but that's not necessarily a bad thing. And, in fact, if you go into the evolution of the code more deeply, people are beginning to suspect it evolved from a simpler one. And there ac...