Question

which of these statements is true about autotrophs, but not heterotrophs?
○ they use sugar and oxygen to make carbon dioxide and water.
○ they use chlorophyll and oxygen to make carbon dioxide and water.
○ they use sunlight, water, and carbon dioxide to make sugars.
○ they use sunlight, water, and oxygen to make chlorophyll.

Explanation:

Autotrophs perform photosynthesis. The process of photosynthesis uses sunlight, water, and carbon dioxide to produce sugars (glucose). Heterotrophs cannot perform photosynthesis. The first option describes cellular respiration (used by both autotrophs and heterotrophs). The second option has an incorrect combination of reactants. The fourth option has an incorrect description of what is made (chlorophyll is a pigment, not a product of the reaction described in that option).

Answer:

They use sunlight, water, and carbon dioxide to make sugars.