Which describes a promoter? a. the first part of an operon that regulates where, when, and to what level a gene is expressed b. the part of an operon that, if attached by a repressor protein, suppresses the expression of a gene c. a cluster of genes that are expressed or repressed as a group d. an enzyme that dna unzip prior to transcription

Jason adds the antibiotic penicillin to a bacterial culture. the bacteria develop genetic modifications in their genome, which gives them resistance to the antibiotic penicillin. what caused this genetic modification?

Some tools have graduations to show multiple measurements. for example, a ruler may have graduations for both millimeters and centimeters. when measuring the length of an earthworm, which graduations would allow for the most accurate measurement? millimeters centimeters decimeters meters

Directions: read the descriptions of the four islands presented in the lesson. 1. list two new traits that each new species of rat might demonstrate as it adapts to the conditions on each island. 2. introduce one of the four new rat species to another island and describe one challenge it would encounter and one success as it adapts to its new environment.