Why do scientists assume the first photosynthetic organisms were anoxygenic?

Which conditions are necessary for natural selection to occur? select all of the answers that apply. a. inheritable adaptations vary among individuals. b. the population size is increasing. c. more individuals are born than can survive. d. fitness varies among individuals. e. the environment changes suddenly and drastically.

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the

Guard cells control which event? the growth of plants capture of solar energy gas exchange in leaves water absorption in roots