Chapter 20.1, Problem 7MI

Summary Introduction

To describe: 

The mechanism how fungi digest their food outside the body.

Introduction:

Fungi are heterotrophs, they may be saprophytes or parasites. Some fungi are in mutual relationships with other organism. The saprophytic fungi obtain nutrients from non-living organic matter, usually dead and decaying plant or animal matter and parasitic fungi draw food from living organisms.

Explanation of Solution

Nutritionally Fungi are heterotrophs. Most of the fungi are saprophytes. They draw food form dead and decaying matters. They secrete hydrolytic enzymes outside the body from their hyphae tips. The enzymes break down or decompose insoluble complex molecules such as polysaccharides, proteins, and lipids into smaller soluble molecules. These molecules are then absorbed as nutrients into the fungal cells. Thus fungi digest their food before they ingest it.

Conclusion

Fungi decompose dead organic matter by releasing digestive enzyme outside their body and digested food then absorbed by the hyphae.