Question

Decomposers of an ecosystem include
A. Microscopic animals
B. Bacteria and fungi
C. Both A and B
D. Bacteria ,fungi and microscopic animals

Answer 1

Decomposers play an important role in the last step of the food chain, converting organic matter into inorganic form, making it available to growers. The topsoil is the main site of decomposition. Thus, the decomposers provide the producer with energy and nutrients. The topsoil consists of fallen dry leaves and debris containing the remains of dead plants and animals.

Complete answer:
Decomposers attack the remains of dead producers and consumers and break down complex organic matter into simpler compounds. Simple organic substances are attacked by various types of bacteria and transformers, converting these organic compounds into inorganic forms suitable for reuse by farmers or green plants. Breakers and transformers play a very important role in maintaining the dynamics of the ecosystem.
Most decomposition is carried out by microscopic organisms, including protozoa and bacteria. Other decomposers are large enough to be seen without a microscope. This includes fungi, as well as invertebrates.
Fungi are important decomposers, especially in forests. fungi do not contain chlorophyll, a green plant pigment that uses the energy of sunlight to produce its own food. Instead, fungi get all of their nutrients from inanimate matter, which is broken down using special enzymes. Fungi are heterotrophic organisms that feed on external sources. The substrate is dissolved and then absorbed. In this way, the fungus breaks down the insoluble substrate into smaller pieces, eventually dissolving the units, and then producing extracellular enzymes that are absorbed by the hyphae.
Certain groups of bacteria play an important role in maintaining soil fertility, as they are involved in the decomposition of nitrogenous organic compounds in the body of plants and animals and the conversion of nitrogen waste into animals and nitrogen in the soil. These are ammonia bacteria, nitrifying bacteria and nitrogen fixing bacteria.

Hence from the above points it’s clear that Bacteria ,fungi and microscopic animals all are decomposers so the correct option is (D).

Note: Decomposers are heterotrophic, meaning they use an organic substrate to obtain energy, carbon and nutrients for growth and development. While the terms decomposer and detritivores are often used interchangeably, detritivores absorb and assimilate dead matter internally, whereas decomposers absorb nutrients directly through external chemical and biological processes.
The main decomposers of waste in many ecosystems are fungi. In contrast to bacteria which are unicellular organisms and also decompose, most saprotrophic fungi grow as a network of branched hyphae. While bacteria limit themselves to growing and eating on exposed surfaces of organic matter, fungi can use their hyphae to penetrate the larger chunks of organic matter beneath the surface.