NEET BIOLOGY

Detailed explanation-1: -Chargaff’s rules states that DNA from any cell of all organisms should have a 1:1 ratio of pyrimidine and purine bases and, more specifically, that the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine.

Detailed explanation-2: -Chargaff’s rules state that in the DNA of any species and any organism, the amount of guanine should be equal to the amount of cytosine and the amount of adenine should be equal to the amount of thymine.

Detailed explanation-3: -Adenine always binds with thymine, and cytosine always binds with guanine. Since certain bases always appear in pairs, they will have equal percentages of the DNA composition. The percentage of adenine will equal the percentage of thymine, and the percentage of cytosine will equal the percentage of guanine.

Detailed explanation-4: -Rule 2. In 1947 Chargaff showed that the composition of DNA, in terms of the relative amounts of the A, C, G and T bases, varied from one species to another. This molecular diversity added evidence that DNA could be the genetic material.

Detailed explanation-5: -Erwin Chargaff (1905-2002) showed experimentally that base compositions actually varied among species. Within any one species, however, the molar ratios [A] = [T] and [C] = [G] are constant, and the proportion of [C+G] < [ A+T ]. These ratios have since been referred to as “Chargaff’s Rules".