Diversity: Fungi
Structure
All fungi are EUKARYOTES.
The nucleus and organelles are located in the cytoplasm, and all are found within a membrane.
Fungi are spore-bearing organisms that reproduce sexually and asexually, and whose usually filamentous branched body is surrounded by walls containing chitin and other complex carbohydrates. Hyphae extend apically. Fungi may be found as aggregations of single cells, known as yeasts. Yeast cells function autonomously.
View
movie of organelle movement within a hypha (352 Kb).
View
movie of hyphal elongation (1.3 Mb).
Question
1Taxonomy
Fungi are divided into five divisions on the basis of their shape, sexual stages, all of which are consistent with sequences of DNA in the chromosomes. The divisions are:
Basidiomycota, Ascomycota, Zygomycota, Glomeromycota and Chytridiomycota.
In practice, fungi are impossible to classify into these
divisions in the absence of molecular data. So organisms isolated from
nature are given a name that reflects their asexual state. The asexual
state may be consistent with a sexual state, but not always. 
View
key to identify fungi isolated from the air.
Nutrition
Fungi gain energy from heterotrophic extracellular digestion. Autotrophy
is unknown in the Fungi kingdom. Most fungi are aerobic, but a few specialised
fungi that occupy anaerobic locations, e.g. the rumen of cows, function
effectively in the absence of oxygen, and a few are facultatively anaerobic,
meaning that they can respire anaerobically and aerobically. to
heterotrophy.
Importance
Fungi are important for:
- digestion of organic matter (also bacteria), to
heterotrophy.
- industrial production (e.g. antibiotics, food acids and additives), to
competition.
- food preservation and spoilage,
- plant health,
- diseases in all organisms as well as biological control of pests, weeds and pathogens,
- recycling of major minerals in the biosphere.
For more information about fungi: to
Fungal Biology.
