BIOL-3350 Chapter Notes - Chapter 10: Defensin, Natural Selection, Horizontal Gene Transfer
Document Summary
Complex adaptations - suites of coexpressed traits that together experience selection for a common function. Adaptations that are made of a number of components that are encoded and controlled by a large number of genes. Complex adaptations are novel traits that require multiple mutations to achieve a fitness advantage. Novel traits are traits that arise de novo (are not inherited from an ancestor) within a lineage and have no obvious counterparts in related lineages. Regulatory network - systems of interacting genes, transcription factors, promoters, rna and other molecules. They function like biological circuits, responding to signals with outputs that control the activation of genes during development, the cell cycle, and the activation of metabolic pathways. Organized into a hierarchy where just a few elements trigger a cascade of gene expression that may involve hundreds of genes. Cascade allows cells to produce a response to an external signal.
