AP BIOLOGY

Detailed explanation-1: -Autotrophs rely on either light or chemical energy to turn CO2 into organic carbon molecules. Photoautotrophs are photosynthesizing organisms such as algae and higher plants that use light for this process. Heterotrophs, in contrast, obtain their chemical energy from preexisting organic molecules.

Detailed explanation-2: -Final answer: They convert carbon dioxide and water into carbohydrates in the absence of sunlight is incorrect.

Detailed explanation-3: -An autotroph is an organism that can produce its own food using light, water, carbon dioxide, or other chemicals. Because autotrophs produce their own food, they are sometimes called producers. Plants are the most familiar type of autotroph, but there are many different kinds of autotrophic organisms.

Detailed explanation-4: -Autotrophs use energy to convert inorganic compounds into organic compounds which they use as fuel. The energy that either comes from sunlight or oxidation, each involved in a different food-producing process, excites the electrons in molecules that trap the energy.