Which type of organism uses sunlight as an energy source and carbon dioxide as a carbon source (example: cyanobacteria)?

• A. Photoheterotroph
• B. Photoautotroph
• C. Chemoheterotroph
• D. Chemoautotroph

Answer: (B)

Verified step by step guidance

1. Step 1: Begin by understanding the terms used in the question. Organisms are classified based on their energy source (sunlight or chemical compounds) and their carbon source (organic compounds or carbon dioxide).
2. Step 2: Define the term 'Photoautotroph.' Photoautotrophs are organisms that use sunlight as their energy source and carbon dioxide as their carbon source. Examples include cyanobacteria, plants, and algae.
3. Step 3: Define the term 'Photoheterotroph.' Photoheterotrophs use sunlight as their energy source but rely on organic compounds (not carbon dioxide) as their carbon source.
4. Step 4: Define the term 'Chemoautotroph.' Chemoautotrophs obtain energy from chemical compounds (not sunlight) and use carbon dioxide as their carbon source.
5. Step 5: Define the term 'Chemoheterotroph.' Chemoheterotrophs obtain energy from chemical compounds and rely on organic compounds as their carbon source. Examples include most animals and fungi.