Question

Define microbial nutritional types with respect to carbon and energy sources. Define and give examples of the following: photoautotroph, chemoautotroph, photoheterotroph, chemoheterotroph, saprobe, parasite.

Answer 1

With respect to carbon-

• Organic- Heterotrophs
• Carbon Dioxide- Autotrophs

With respect to energy-

• Light- Phototrophs
• Chemical compounds-Chemotrophs.

Photoautotrophs- these are the organisms that uses the light energy to prepare their own food, Examples are plants and all photosynthetically active organisms.

Chemoautotrophs- They use inorganic energy sources to synthesize organic compounds from carbon dioxide.Examples are-Archibacteria

Photoheterotrophs-They use light as energy source, but cannot use carbon dioxide as their sole carbon source.example- Heliobacteria

Chemoheterotrophs-These organisms utilizes chemical energy to produce acrbohydrates.Example-hydrogenovibrio crunogenus.

Saprobe-they derive their nutrition from dead and decaying organisms. example-Fungus

Parasite- the organisms which lives inside another organisms. They derive their nutrition from that organisms.Example-tapeworm , Barnacles.