Which type of organisms primarily take in atmospheric carbon dioxide for the process of photosynthesis?

• A. Decomposers
• B. Heterotrophs
• C. Parasites
• D. Autotrophs

Answer: (D)

Verified step by step guidance

1. Understand the process of photosynthesis: Photosynthesis is the process by which organisms convert light energy, water, and carbon dioxide into glucose and oxygen. This process primarily occurs in organisms that can produce their own food.
2. Define autotrophs: Autotrophs are organisms that can synthesize their own food using inorganic substances like carbon dioxide and water, typically through photosynthesis. Examples include plants, algae, and some bacteria.
3. Eliminate incorrect options: Decomposers break down dead organic matter, heterotrophs consume other organisms for energy, and parasites rely on a host for nutrients. None of these groups perform photosynthesis to produce their own food.
4. Connect autotrophs to atmospheric carbon dioxide: Autotrophs take in atmospheric carbon dioxide (CO₂) as a key reactant in the photosynthesis process. The chemical equation for photosynthesis is: $\mathrm{6CO}{2}_{}+\mathrm{6H}{2}_{}O\to C{6}_{}H{\mathrm{12}}_{}O{6}_{}+\mathrm{6O}{2}_{}$.
5. Conclude that autotrophs are the correct answer: Since autotrophs are the only organisms capable of directly using atmospheric carbon dioxide for photosynthesis, they are the correct answer to the question.