What is the name of the process by which molecules naturally flow from an area of higher concentration to one of lower concentration?
a. respiration
b. transfusion
c. dialysis
d. diffusion

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

Match the correct terms to their descriptions a system in which only energy but not matter is exchanged frozen water in snow part of geosphere that includes only soil a thin layer between the troposphere and the stratosphere cryosphere tropopause closed system pedosphere

The table below shows data for a population of fish in a pond. fish body color # of fins scales? tail shape a silver 4 yes fan b pink 4 yes flat c black 4 yes fan d orange 4 yes flat e orange 4 yes fan f silver 4 yes flat which of the above characteristics would be most in developing a classification system for the fish? a. body color and tail shape b. presence of scales and tail shape c. body color and number of fins d. number of fins and presence of scales