Fungi

Fungi: in air, in water, on land, in soil, and on plants and animals... everywhere!
-Determine the types of plants and eventually the types of animals in an area
-Some are microscopic, others are extremely large
-Million plus species of fungi, only identified 5% of all fungi

Body plan-
-Almost entirely multicellular (composed of filaments called hyphae), some have two nuclei (multinucleate)
-Rarely unicellular
Example multicellular: mushrooms
Example unicellular: yeast (Saccharomyces cerviseae)


Divergent event-
-1 billion years ago
-Fungal cell wall composed of glucans and chitin – the only organisms that combine these two molecules in their cell walls
-More complex than protists, but protists were the start of fungi development
-Most fungi share a common ancestor with kingdom Animalia, not Plantae (surprisingly)

Metabolism-
-Heterotrophic – absorption
            -saprophytic – secrete enzymes to break down dead organic matter
            -parasitic – obtain nutrients from living hosts

Digestion-
-Extracellular – secrete enzymes and absorb nutrients provided

Circulation - no heart

Respiration-
-yeast requires anaerobic respiration
            -use glucose and oxygen to produce carbon dioxide, water, and energy

Nervous - no brain

Reproduction-
-sexual or asexual (spores, budding, binary fission)
            -zygote is the only diploid cell, two nuclei do not fuse – they coexist (dikaryoitic stage, unique to fungi)

Examples-
-Penicillium

-Rhizopus (mold on breads, fruits and vegetables)
 40x

Phylum: Basidiomycota
-Most mushrooms, shelf fungi, and puffballs
-Most familiar, called “club fungi”
            -account for almost a third of all identified fungi
-Fruiting bodies are visible
-Many are poisonous (genus Amanitas)
Example - Amanita Muscaria - hallucinogenic mushroom, often for drug-use


Phylum: Zygomycota
-Black bread mold
-Decomposes bread, fruits, vegetables, and decaying animals
-Produces a fuzzy, black growth on its substrate
-Form a zygospore as part of their sexual reproduction, but can reproduce asexually also
-Harmful if eaten!


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