Which of the following mutations would make Lac operon regulation unresponsive to glucose levels.

a. A mutation in CRP that makes it unable to bind cAMP
b. A mutation in LacI that makes it unable to bind lactose
c. A mutation in LacI that makes it unable to bind glucose
d. A mutation in CRP that makes it unable to bind glucose

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

Which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements. which statements about the fluid mosaic structure of a membrane are correct? select the three correct statements. the framework of a membrane is a bilayer of phospholipids with their hydrophilic heads facing the aqueous environment inside and outside of the cell and their hydrophobic tails clustered in the center. because membranes are fluid, membrane proteins and phospholipids can drift about in the membrane. the diverse proteins found in and attached to membranes perform many important functions. the kinky tails of some proteins keep the membrane fluid by preventing the component molecules from packing solidly together. membranes include a mosaic, or mix, of carbohydrates embedded in a phospholipid bilayer.

Veins have a much lower blood pressure than arteries. which of these prevents backflow of blood in veins? a. pressure applied by the heart b. one–way valves in veins c. thin muscular walls of veins