Question

How do fungi absorb nutrients?

Answer 1

Hint: Fungi are heterotrophic (cannot manufacture their own food) in nature. They utilize complex organic compounds as the source of carbon and nitrogen. They then absorb these nutrients and obtain nutrition. Fungi derive nutrients from dead and decaying organic matter, mainly plant material.

Complete answer:
In fungi first the food is digested and then ingested. Fungi secrete exoenzymes on their food material or external environment and then they process nutrients in the environment. The small molecules are then obtained by the external digestion and are then absorbed by the large surface area of mycelium.
Fungi derive nutrients from dead and decaying organic matter, mainly plant material.
Fungal exoenzymes can break down insoluble polysaccharides (like cellulose and lignin), into readily absorbable glucose molecules. This results in the release of carbon, nitrogen and other elements into the environment. Fungi also contribute to bioremediation. Some species of fungi help to degrade diesel oil and certain aromatic hydrocarbons. Some species of fungi also take heavy metals (like cadmium and lead).

Some fungal species are parasitic in nature, Example: Athlete’s foot and Candidiasis (thrush).
In nitrogen poor environments, some fungi way out to nematode predation. Arthrobotrys species of fungi possess various ways to trap nematodes. Species of Arthrobotrys constrict rings within the hyphae network. When these rings touch the nematode, they swell and grip the nematode in a tight hold. There are certain species of fungi which possess haustoria. Haustoria penetrates the tissue of the host by enlarging specialized hyphae. Haustoria penetrates the host tissue, releases the digestive enzymes within the host’s body, and then the digested nutrients are absorbed.

Note: Fungi first digest food and then ingest it, unlike other animals, where ingestion precedes digestion. Fungi contribute to bioremediation and thus help to clean the environment. Some species of fungi also take up heavy metals.