About Lesson
Characteristics of DNA
- DNA molecules have distinctive base composition.
- Four nucleotide bases of DNA occur in different ratios in the DNAs of different organisms and that the amounts of certain bases are closely related.
- Base composition of DNA generally varies from one species to another.
- DNA specimens from different tissues of same species have same base compositions.
- Base composition of DNA of a species doesn’t change with organisms age, nutritional state or changing environment.
- In all cellular DNA, A=T and G ≡ C