Yeast mutants that are defective in their ability to complete cell division have led to the discovery of many genes that control the cell-division cycle—the so-called Cdc genes—and have provided a detailed understanding of how these genes, and the proteins they encode, actually work.
举一反三
- Tumor suppressor genes encode proteins that normally restrain cell division. Mutation in one or more of these genes can lead to tumor formation.
- In positive regulation, most of the genes are usually inactive (that is, RNA polymerases do not bind to the promoters) and the cell synthesizes only the activator proteins needed to promote transcription of the subset of genes required in the cell at that time.
- If two genes from a parent cell are on the same chromosome, which of the following best explains why the daughter cells may not have the same alleles as the parent for both genes? A: they are linked genes B: they are unlinked genes C: crossing-over D: genetic mutation
- Stability genes (also called caretaker genes) encode proteins that function in the repair of major genetic defects that result from aberrant DNA replication, ionizing radiation, or environmental carcinogens.
- The stages which a cell passes from one cell division to the next is called () A: cell cycle B: life cycle C: energy cycle D: regeneration<br/>cycle