AP BIOLOGY

Detailed explanation-1: -Some varieties of bacteria use light to create their own food, just like organisms that use photosynthesis. However, these bacteria are not autotrophs, because they must rely on chemicals besides carbon dioxide for carbon. These strange bacteria are called photoheterotrophs.

Detailed explanation-2: -Examples of photoheterotrophic organisms include purple non-sulfur bacteria, green non-sulfur bacteria, and heliobacteria.

Detailed explanation-3: -Photoheterotrophs, in particular, are microorganisms that derive their carbon requirements mainly from organic compounds in their environment. These organisms are purple non-sulfur bacteria, green non-sulfur bacteria, and heliobacteria.

Detailed explanation-4: -Hint: Photoautotrophs are organisms, such as plants that can synthesize their own food from inorganic material in the presence of light whereas photoheterotrophs are those organisms that use light as a source of energy.

Detailed explanation-5: -The word photoautotroph is a combination of autotroph, the word for an organism that makes its own food, and the prefix photo-, which means “light”. Green plants and photosynthetic bacteria are examples of photoautotrophs.