Chapter 10 Textbook Genetics

1. Although both proteins and nucleic acids were initially considered as possible candidates for genetic material, proteins were initially favored.

2. By 1952, transformation studies and experiments using bacteria infected with bacteriophages strongly suggested that DNA is the genetic material in bacteria and most viruses.

3. Although initially only indirect observations supported the hypothesis that DNA controls inheritance in eukaryotes, subsequent studies involving recombinant DNA techniques and transgenic mice provided direct experimental evidence that the eukaryotic genetic material is DNA.

4. RNA serves as the genetic material in some bacteriophages as well as some plant and animal viruses.

5. As proposed by Watson and Crick, DNA exists in the form of a right-handed double helix composed of two long antiparallel polynucleotide chains held together by hydrogen bonds formed between complementary, nitrogenous base pairs.

6. The second category of nucleic acids important in genetic function is RNA, which is similar to DNA with the exceptions that it is usually single stranded, the sugar ribose replaces the deoxyribose, and the pyrimidine uracil replaces thymine.

7. Various methods of analysis of nucleic acids, particularly molecular hybridization and electrophoresis, have led to studies essential to our understanding of genetic mechanisms.

Insights and Solutions

The current chapter, in contrast to previous discussions, does not emphasize genetic problem solving. Instead, it recounts some of the