Question

In an ecosystem, bacteria are
A. Microconsumers
B. Macroconsumers
C. Primary consumers
D. Secondary consumers

Answer 1

Hint:- Ecosystem is the sum of abiotic and biotic components of a specific geographical area. It is a dynamic entity that involves intra as well as interspecific interactions, energy flow, material cycling, etc. The term ecosystem was given by A.G. Tansley.

Complete Answer:- The consumers are the heterotrophic component of the ecosystem as they consume either the readymade organic food or decompose the complex organic foods. These are also known as consumers. They do not have chlorophyll, so cannot synthesize their own food. Depending upon their size, heterotrophs are divided into two main categories:
Macroconsumers- These include the animals, which eat or ingest the producers directly or indirectly. These are also known as phagotrophs. Depending upon the nature of the food they consume, they are divided into four categories:
Primary consumers- These include the herbivores which directly eat upon the plants.
Secondary consumers- It includes the primary carnivores that eat upon the herbivorous animals.
Tertiary consumers- These include the secondary carnivores that eat upon secondary consumers.
Quaternary consumers- It includes the tertiary or top carnivores that eat upon the tertiary consumers.
Microconsumers- These are also called decomposers or saprotrophs or reducers that break down the complex organic compounds of dead bodies of both plants and animals. They absorb some of the decomposed products while releasing most of the inorganic compounds into the environment from where these are reused by producers. So these help in material cycling. It includes non-green microscopic organisms like bacteria and fungi which secrete digestive enzymes to digest the organic compounds externally.

So the correct answer is A. Microconsumers.

Note:- An ecosystem is composed of the abiotic physico-chemical environment and biotic assemblage of plants, animals and microbes. These components collectively form an ecosystem stable and self-sufficient unit.