AP Biology Chapter 18 Gene Regulation Flashcards
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| 685276192 | Operon model | controls gene expression in bacteria | |
| 685276193 | Operator | the regulatory "switch"; a segment of DNA positioned within the promoter | |
| 685276194 | Operon | the entire stretch of DNA; includes the operator, the promoter, and the genes that they control | |
| 685276195 | Negative Operon control | gene that is normally on is turned off | |
| 685276196 | Positive Operon control | gene that is normally off is turned on | |
| 685276197 | What type of operon control do the regulation of the trp and lac operons involve? | Negative control, because operons are switched off by the active form of the repressor | |
| 685276198 | repressible operon | normally on; binding of a repressor to the operator shuts off transcription (trp operon) | |
| 685276199 | Inducible operon | normally off; an inducer inactivates the repressor and turns on transcription (lac operon) | |
| 685276200 | Repressible enzymes | function in anabolic pathways; their synthesis is repressed by high levels of the end product | |
| 685276201 | Inducible enzymes | function in catabolic pathways; their synthesis is induced by a chemical signal | |
| 685276202 | What protein is an activator of transcription, and subjects operons to positive control? | Catabolite Activator Protein (CAP) | |
| 685276203 | What is the preferred food source of E. Coli? | Glucose | |
| 685276204 | When glucose in E. Coli is scarce, what is activated by binding with cyclic AMP? | CAP | |
| 685276205 | When CAP attaches to the promoter of the lac operon, what occurs? | the affinity of RNA polymerase is increased, which accelerates transcription | |
| 685276206 | What happens in E. Coli when glucose levels increase? | CAP detaches from the lac operon, and transcription returns to a normal rate | |
| 685276207 | What is the purpose of CAP? | helps regulate other operons that encode enzymes used in catabolic pathways | |
| 685276208 | A Repressor is a product of what? | a separate regulatory gene | |
| 685276209 | Why can't transcription factors bind to a promote packaged in a nucleosome? | Nucleosomes block promoters | |
| 685276210 | Basal transcription factors | provide alignment for RNA polymerase; establish productive initiation | |
| 685276211 | Specific transcription factors (activators) | stimulate higher levels of transcription that basal levels | |
| 685276212 | Enhancers | binding site of specific transcription factors; DNA bends to form a loop, positioning the enhancer close to the promoter | |
| 685276213 | Three stages of embryonic development | cell division, cell differentiation, and morphogenesis | |
| 685276214 | Cell differentiation | the process by which cells become specialized in structure and function | |
| 685276215 | Morphogenesis | the physical processes that give an organism its shape | |
| 685276216 | Cytoplasmic determinants | The maternal substances in the egg that influence the course of early development by regulating the expression of genes that affect the developmental fate of cells. | |
| 685276217 | Induction | signal molecules form embryonic cells cause transcriptional changes in nearby target cells | |
| 685276218 | Cell determination | commits a cell to its final fate; before cell differentiation | |
| 685276219 | MyoD | one of several "master regulatory genes" that produce proteins that commit the cell to becoming skeletal muscle; transcription factor that binds to enhancers of various target genes | |
| 685276220 | Pattern formation | development of a spatial organization of tissues and organs (body plan) | |
| 685276221 | embryonic lethals | Mutations with phenotypes leading to death at the embryo or larval stage. | |
| 685276222 | Maternal effect genes | encode for cytoplasmic determinants that initially establish the axes of the body of Drosophila | |
| 685276223 | egg-polarity genes | Another name for maternal effect genes, these genes control the orientation (polarity) of the egg and the fly | |
| 685276224 | bicoid | A maternal effect gene that codes for a protein responsible for specifying the anterior end in Drosophila. | |
| 685276225 | Three ways proto-oncogenes can be changed into oncogenes | Movement of DNA within the genome, Amplification of a proto-oncogene, point mutations | |
| 685276226 | Movement of DNA within the genome causes? | if it ends up near an active promoter, transcription may increase | |
| 685276227 | Amplification causes? | increases the number of copies of the gene | |
| 685276228 | Point mutations cause? | an increase in gene expression | |
| 685276229 | TATA Box | aligns transcription factors within the promoter site |