The table below shows the age of fossils found in four separate layers of undistributed rock: A layer a. B LAYER B. C. LAYER C. D LAYER D

The rate at which molecules water and oxygen can enter a cell is determined by the-

Which muscle is responsible for inhalation ?

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.