CHAPTER OUTLINE 1.1The nature of biological information 1.2How information becomes biological form 1.3Genetics and evolution 1.4Genetics has provided a powerful new approach to biological research 1.5Model organisms have been crucial in the genetics revolution 1.6Genetics changes society 1.7Genetics and the future
DNA replication is the basis for the perpetuation of life through time
Question When referring to two homologous chromosomes in an individual diploid cell, which of the following statements is most accurate? a) These chromosomes will normally carry the same genes, in the same order. b) These chromosomes will normally be identical in sequence. c) These chromosomes will normally carry the same genes, but often not in the same order. d) All of the above.
Many human diseases are caused by mutations in single genes
Evolutionary tree based on comparisons of cytochrome c DNA
Two different genetic approaches Forward genetics (from phenotype to gene) ID the mutant phenotype ID morphological, physiological, developmental differences ID the gene (DNA sequence) Reverse genetics (from gene to phenotype) ID a gene Mutate, knockout or over- express the gene Analyze morphological, physiological, or developmental effects (the phenotype)
Question Experiments where researchers knock out a target gene in a model organism and analyze the effects of this manipulation to get clues regarding the function of the target gene are examples of a) classical genetics. b) developmental genetics. c) forward genetics. d) mendelian genetics. e) reverse genetics.
Probes can be used to detect specific macromolecules
Question Which of the following chemical characteristics of DNA forms the basis for hybridization technologies to detect specific DNA sequences? a) Antibodies that recognize DNA bind tightly to it, forming highly specific probes. b) Antigen-antibody complexes react specifically with DNA and form the basis for Western blotting. c) Single-stranded DNA will bind tightly to a sequence identical to it. d) Single-stranded DNA will bind tightly to a sequence complementary to it. e) No two DNA sequences are exactly identical.
PCR primers detect and amplify a specific genomic region
Some organisms used as models in genetic research
Model Systems Be prepared to present to the class the model system whose genus name begins with the letter closest to the first letter of your last name. Arabidopsis thaliana Drosophilia melanogaster (fruit fly) Saccharomyces cerevisiae (yeast) Neurospora crassa (fungi) E. coli (bacteria) C. elegans (worm) Mus musculus (mouse)