Question

The fungi and bacteria are considered as
A.Osmotrophs
B.Halophytes
C.Mixotrophs
D.None of the above

Answer 1

Hint: Most of the fungi and bacteria grow over rotten dead or decaying matter. They take up the dissolved organic compounds through osmosis. The plasma membranes produce the concentration gradient and absorb the food.

Complete answer:Bacteria are unicellular prokaryotic organisms whereas fungi are unicellular as well as multicellular eukaryotic organisms. Most of the bacteria and fungi are heterotrophs. This means that they cannot produce their food on their own and thus are dependent on other organisms for their nutrition. The cell membranes of bacterial as well as fungi perform osmosis to feed.
Fungi and bacteria prefer to grow in humid and cold environments. Several bacteria and fungi are found growing over rotten logs, withered rocks, etc. They prefer the dead and decaying matter to grow upon. This niche provides bacteria and fungi with dissolved organic solids already partially broken up into simpler compounds. The bacterial and fungal cells perform osmosis to suck up the partially broken decaying organic molecules as nutrition. Thus fungi and bacteria are Osmotrophs as they acquire food through osmosis. Some of the higher organisms like mollusks, coral, and sponges also perform osmosis and are called osmotrophs.
Halophytes on the other hand refer to the plants that grow in high saline waters or soil. Most of the free-living protozoans are mixotrophs. This means that some of them perform photosynthesis to obtain nutrition and some of them depend on symbiosis.
So, the correct answer is option A i.e., Osmotrophs

Note: Cellular layers of bacterial and fungal cells ensure proper diffusion of nutrients from the rotting matter. Osmotrophs form a major portion of degrading organisms. Without the presence of osmotrophs, the forests will turn into heaps of waste including fallen leaves, dead organisms, etc. Thus, the osmotrophs form a key component of the ecosystem.