During cellular respiration, every living thing in this food web uses gas and releases back into the environment.
a)
carbon dioxide: oxygen
b)
oxygen: carbon dioxide
c)
carbon dioxide: hydrogen
d)
carbon dioxide: water vapor

Which statement best explains why cells were observed in more detail using a compound microscope than a simple microscope? a compound microscope has greater magnification ability than a simple microscope. the compound microscope was invented before the simple microscope. a compound microscope is much easier to manufacture than a simple microscope. compound microscopes were more common than simple microscopes.