What type of barrier led to reproductive isolation of the two tree frogs Behavioral
Temporal
Habitat
Unable to determine

Consider the model of the oxygen cycle on earth. the majority of earth's oxygen reservoirs are found in the a) atmosphere. b) biosphere. c) hydrosphere. d) lithosphere.

In the respiration-photosynthesis cycle shown above, what are the products of cellular respiration that belong in box 2?

During photosynthesis, hydrogen ions are most directly used to in the chloroplast pictured above. a) make glucose b) make chlorophyll c) produce carbon dioxide d) drive the production of atp