This figure illustrates 3 hypotheses of how a cancer stem cell may arise: (1) A stem cell undergoes a mutation, (2) A progenitor cell undergoes two or more mutations, or (3) A fully differentiated cell undergoes several mutations that drive it back to a stem-like state.
Answer :Erwin Chargaff a Biochemist
Explanation:
He formulated the base paring of double helix of DNA. He reasoned that since the percentage of four DNA bases are of this proportions in human;
Adenine=30.9% and Thymine =29.4%;
Guanine=19.9% and Cytosine =19.8%
Then, the amount of adenine will always be equal to thymine,
And the amount of Guanine equals to cytosine based on this percentages of distribution.
(Adenine and Guanine are large, molecule of Purines, while thymine and Cytosine are Pyrimidine)
He concluded (although scientist believed, he did not explicitly stated this) that this should be the base paring patterns in DNA molecule. This is the first Chargaff Rule.
His second rule is that the DNA composition, in the relative amount of the four bases Adenine, Thymine, Cytosine and Guanine varies in proportion from one organisms to another. And this is the basis of molecular diversity.
The word you're looking for is the Bowen's reaction.
Hope it helped!
Cells need both genes, and each cell inherits half of the genes from both cell parents.
A red blood cell's function is to transport oxygen.
