Arose in the oceans over 1.4 billion years ago.
Colonized land over 500 MYA.
Difficult to assess fossils, as soft bodies don’t fossilize well.
Increased in diversity (and size) on land.
Fungi are mostly chemoheterotrophs.
Can be multicellular or unicellular.
Most species are sessile: no active movement.
Fungi are decomposing or parasitic saprophytes:
Grow upon their food, secrete digestive enzymes, absorb nutrients.
Despite appearances, fungi are more closely related to animals than they are to plants.
Fungi are essential decomposers.
Some fungi parasitize animals and plants (rusts, bights, smuts, ergot).
In humans: athlete’s foot, ringworm.
Fungal fruiting bodies are often edible (morels, truffles, mushrooms).
Some may be toxic, however.
Yeast create CO in2the process of anaerobic (without O ) f2rmentation.
Used to make alcoholic drinks, cheese, yogurt, vinegar, pickles, leaven bread.
Penicillin and other fungus-derived chemicals are important antibiotics.
Fungal cell walls are made of strong flexible chitin, not cellulose.
Like plants, fungi have large surface area: volume ratios
Helps absorb nutrients.
Most multicellular fungi are made of hyphae, long strands of cells.
Hyphae form a feeding body, the mycelium (plural mycelia).
Structures visible above ground are the fruiting body (reproductive).
Fungi need to spread in order to colonize scarce food resources.
Decomposable food is widely spread in nature.
Must disperse widely in large numbers.
Catch the wind like pollen of seed plants.
Multicellular fungi reproduce via spores, produced sexually or asexually. Unicellular fungi reproduce asexually by budding.
Unlike mitosis, this may not evenly subdivide the cytoplasm of the resulting cells.
Smallest and simplest fungi.
The oldest and most basal fungal division.
Mostly aquatic parasites
Gametes have flagella for movement.