Junk DNA: goodbye! (Introduction)

by Balance_Maintained , U.S.A., Wednesday, June 25, 2014, 11:54 (3805 days ago) @ David Turell
edited by unknown, Wednesday, June 25, 2014, 12:14

There is a secondary effect as well that is not mentioned at all. The more functional DNA that they discover the greater the gap between humans and other species becomes. Traditionally, they only compared functional DNA when measuring the disparity between species.-Right now, even an extremely conservative estimate of differentiation between base pairs is likely in the 500,000,000 base range, and one base pair is enough to change an essential function. -->>Point Mutations are changes involving only one base pair of the DNA. (Very small mutations--ie, two or three base pairs--are generally also considered point mutations, although they don't strictly meet the definition.)
1.
Base substitutions involve the replacement of one base (and its complementary partner) by one of the other bases (and its complementary partner). Base subsitutions affect only the amino acid coded for by the codon affected.
a.
Transition mutations involve replacing a purine with another purine (and its partnering pyrimidine with another pyrimidine), or replacing a pyrimidine with a pyrimidine (and its partnering purine with another purine). For example, if an A-T pair is replaced by a G-C pair, this is a transition.
b.
Transversion mutations involve replacing a purine with a pyrimidine (and its partnering pyrimidine with a purine), or replacing a pyrimidine with a puring (and its partnering purine with a pyrimidine). For example, if an A-T pair is replaced by either a T-A pair or a C-G pair, this is a transversion.
2.
Frame shifts are created when one or a few bases are inserted or deleted, thus altering the ultimate reading frame of the ribosome. Frame shift mutations affect all of the protein following the position of the inserted or deleted base. Ribosomes read in a strict 3-base-codon frame, regardless of whether the final amino acid sequence "makes sense." --Since even one base change can change the environment, and the environment can change the expression, 500,000,000 differences in base pairs is nothing to sneeze at.

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What is the purpose of living? How about, 'to reduce needless suffering. It seems to me to be a worthy purpose.