The mode of nutrition is fungi heterotrophic.  

They cannot synthesize their own food and are dependent on other ‘organisms’ for their carbon source. They perform extracellular digestion by releasing enzymes into their environment and obtain organic and inorganic nutrients through absorption.  

There are three main ways of obtaining nutrition:  

(i) Saprotrophic: decomposition of ‘dead organic matter’.  

(ii) Parasitic: feeding from a living host.

(iii) Mutualism: living in a mutually beneficial interaction with another organism. (Example: lichen is a mutualism between fungi and algae).

Mode of Nutrition in Fungi

Fungi are heterotrophic, which means they cannot produce their own food. They obtain their nutrients from organic matter in their environment. The mode of nutrition in fungi is saprophytic, parasitic, and symbiotic.

Saprophytic Nutrition

Fungi obtain their nutrients by decomposing dead organic matter. They secrete enzymes that break down complex organic compounds into simpler compounds, which are then absorbed by the fungi. Fungi play a crucial role in recycling nutrients in ecosystems, as they break down dead organic matter and release nutrients back into the soil for other organisms to use.

Parasitic Nutrition

Some fungi are parasites, which means they obtain their nutrients from living organisms. Parasitic fungi can infect plants, animals, and even other fungi. They penetrate the host's tissues with specialized structures called haustoria, which allow them to absorb nutrients from the host.

Symbiotic Nutrition

Fungi can also form mutually beneficial relationships with other organisms. For example, mycorrhizal fungi form symbiotic associations with the roots of plants. The fungi provide the plant with nutrients such as phosphorus and nitrogen, while the plant provides the fungi with carbohydrates produced through photosynthesis.

Conclusion

In conclusion, the mode of nutrition in fungi is heterotrophic, and they obtain their nutrients through saprophytic, parasitic, and symbiotic relationships. Fungi play an essential role in nutrient cycling and maintaining the balance of ecosystems.