How do the cells in a fish react when it moves from salt-water to freshwater?

One of the purposes of transcription is to produce a sequence of bases that

Identify the area on the image where the force of attraction is the strongest.

What is a population? a. all the members of the same species living in the same ecosystem at the same time b. the number of a species living in the same ecosystem over a period of time c. the total number of organisms living in an ecosystem at a point in time d. all the members of a food web in the same ecosystem