what gas has increased in concentration in the atmosphere since the
beginning of the industrial revolution?
a carbon dioxide
b oxygen
c neon
d nitrogen

Which statement is true about the cell theory? a) it is well-supported by evidence. b) it is unchangeable and permanent.

The image shows the evolution of a species of fish. a few fish from a population developed different social behaviors and evolved into different species. two fish according to the image, the fish underwent . the new species of fish had mating seasons that were different from that of the original fish. because of the differences in mating seasons, the fish underwent reproductive isolation. this mode of isolation would be .

Which statement is true for bacteria a. bacteria have complex internal structures b. all bacteria are spiral in shape c. all bacteria cause disease in animals d. bacteria break down some foods