BISC 121Lg Chapter Notes - Chapter 16: Thymine, Nuclease, Helicase
Document Summary
It was originally thought that proteins were genetic material. Transformation- change in genotype and phenotype because of assimilation of external. Dna by a cell: griffith discovered this while conducting pneumonia research. Virus- basically just dna or rna that needs to infect a cell to reproduces: hershey and chase discovered that phages (viruses) reproduce by injecting their. This led to the realization that dna is genetic material, not proteins. Dna is made up of a nitrogenous group, a pentose (5 carbon sugar, in this case deoxyribose) and a phosphate group (adenine, thymine, guanine, or cytosine) Chargaff proved that dna is molecularly diverse, and therefore a better candidate for genetic material than protein. Chargaff found that the amounts of adenine in dna equal the amounts of thymine and that the amounts of guanine equal the amounts of cytosine. Chargaff"s rules: base composition of dna varies between species, % of adenine = % of thymine and % of cytosine = % of guanine.
