Proteins are used for many structural functions such as in the actin and myosin in muscle or as a part of the cytoskeleton scaffolding that maintains cell shape. what other main function do proteins serve? a. as enzymes to control the rate of reactions and regulate cellular activity b. as waterproof membranes to regulate the transport of molecules in and out of the cell c. as coding for genotypic expression and phenotypic traits d. as cellulose to form the major structural component of plant cell walls

1. variations in a population of moths allow for some of its members to be able to adapt to environmental changes. the better adapted of the moths will be able to survive the change and thus prevail as the “fittest” of the species. (a) describe three mechanisms in which variation can occur within a species population. (b) explain which mechanism or mechanisms would be responsible for the survival of a population of peppered moths better than white moths in an environment affected by industrial soot. justify your answer.

Which of these parts of the membrane large moecules pass through it ?

What might explain the real-world results, show in the graph to the right, for one class of twenty students? check all that apply.