Question

Detritus food chain begins with
A. Bacteria
B. Viruses
C. Algae
D. Protozoa

Answer 1

Hint: Detritus food chain begins with dead organic matter that is decomposed by decomposers. Decomposers are unicellular prokaryotic microorganisms which were among the first life to appear.

Complete answer:
Detritus food chain starts with dead organic matter that is decomposed by the decomposers. Decomposers are usually heterotypic organisms mainly bacteria and fungi. Therefore the energy present in the dead decayed matter passed into them, and then these are consumed by smaller carnivores. Smaller carnivores than consumed by other larger carnivores.
A detritus food chain involves –
Detritus food chain follows a sequence of organisms which involves food energy transfer from producers to consumers through a series of organisms. Each level in the food chain where the transfer of energy takes place is called trophic level.

Hence, the correct answer is option (A).

Additional information:
There are three main types of food chain – Grazing food chain, Detritus food chain, and parasitic food chain. Grazing food chain consists of producers, consumers, and decomposers. Sometimes detritus food chains may be connected with grazing food chains, because some organisms eat detritus food chain organisms. If two food chains are interconnected, it is called food web.

Note: In each food chain energy flow is unidirectional, so once the energy passes it never comes back to the lower level. A large fraction of energy flows through the detritus food chain only than the grazing food chain. The major flow of energy in the aquatic ecosystem flows through the grazing food chain. Microbes like bacteria and fungi are not involved in parasitic food chains.