What major process that requires oxygen do organisms perform to produce energy?

The observations of hooke and van leeuwenhoek documenting the existence of microscopic cells formed the basis of what important theory? a. the cell theory stating that all living things are composed of cellsb. the theory of spontaneous generation, which held that life forms could arise spontaneouslyc. the theory of chemotherapy, or use of antimicrobials to destroy pathogenic organismsd. the germ theory of disease and causative agents

Compare the depth of field when focusing with low power and high power. which power has the greater depth of field?

Quick asap will give brainiest ! what best describes the same pattern of tides on earth throughout the day? neap tides spring tides semidiurnal tides nocturnal tides