In an aerosol can used for spray paint, a highly compressed "propellant" move the liquid into a "dip tube" so that it can be sprayed out. the valve through which the liquid sprays is usually closed, but when it is pressed down, it opens and allows material to pass through.

What are genotypes? what are phenotypes?

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.

The cluster of developing cells from conception until birth is called an