The nervous system communicates through electrical impulses and the communication is very fast. It works in a relay fashion, from point to point comparable to the way the old telephones systems used to work.
The endocrine system communicates by chemical signals via the bloodstream. Hormones are secreted into the blood and extra cellular fluids, then transported to target cells, which must bear a receptor to be able to bind to a specific hormone, and respond.
Hormones are chemical messengers secreted into blood or extracellular fluid that affect the function of other cells.
Endocrine communication is not quite as fast as the nervous system communication
Answer: A group that closet matches characteristics
Explanation:
A representative sample is a group that closely matches the characteristics of its population as a whole. In other words, the sample is a fairly accurate reflection of the population from which the sample is drawn.
Answer: Option C.
Population density is the total number of organisms within a fixed area.
Explanation:
Population density is the total number of organisms per unit area. Population density is calculated by dividing the number of organisms by the unit area either in square kilometers, squaremeters, square miles.
Population density =number of organisms ÷ unit of land area.
Genetic traits that survive through selection increase throughout a population.