Post on 16-Jan-2016
transcript
Chapter 23: Fungi
Fungus Diversity
•Identify what fungi are. •Describe habitats of fungi. •Outline the structure of fungi. •Describe fungi reproduction. •Summarize the evolution of fungi. •Give an overview of fungi classification.
You should be able to:
What is a Fungus?
Not a plant!!!– Heterotroph - No chlorophyll
therefore a– Saprobe – feeds on dead or
decaying matter
Eat by absorbing nutrients (decomposer)
– extracellular digestion, - Use hyphae for digestion that takes place outside of the body.
– Enzymes that break down nutrients then it is absorbed. (plants do not absorb nutrients)
Nutrition (Gets its food: )
Symbiosis
- Two organisms live in association together– Types of Symbiosis
• Mutualism• Parasitism• commensalism
Parasitic Fungus
- Parasite - live off of living organism Ex. athletes foot
- extracellular digestion
What it looks like under skin.
Ringworm
Mutualistic Fungus
Lichens and Mycorrizae
Lichens
- mutualism between a fungus and an algae- fungus- moisture, algae- food- Pioneer- one of first organisms to move into an areaenvironmentally sensitive
Mutualism: Lichen
Mycorrhizae
- mutual relationship between plant roots and fungi (90%)- increase absorption ability of roots
fungus benefit - nutrients and water
Structure of Fungus
• Cell wall made out of Chitin
Hyphae- reproductive filamentsMycelium- visible mass of hyphae
• Ex.Mushroom
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- Hyphae and a mycelium
Reproduction of Fungus
Asexual – Fragmentation ,budding, – Produce spores
Spores
- Sporangium
- structure producing spores- sexual reproduction- 3 types- basis of classification
Adaptations
- spores- resistant- spores carried everywhere- huge numbers- puffball= trillion spores- warm, moist conditions
Zygote Fungus
Phylum – ZygomygotaExample: Bread MoldSpores are made by both asexual and sexual repro.Sexual Reproductive structure:– Sporangium
Distinct structures of:– Rhizoids – hyphae that
anchor the fungus– Stolon – mycelia that grow
along the surface
Note Rhizoids and Stolons:
You are looking at sporangia – contains spores
Sac Fungi - Ascomycota- colorful molds, dutch elm disease, apple scab, morels, truffles, yeast, and cup fungi
- Ascus – reproductive structure in sac fungus
- spore producing sac- sexual reproduction
Club Fungi- Basidiomycota
- mushrooms, puffballs, brackets, rusts and smuts, toadstools
- Basidia
- spore producing structures- gills, cap, stipe
- only sexual reproduction
Imperfect Fungi
Asexual reproduction onlyExamples:Penicillium – Aspergillus – used to
make soy sauce and citric acid
– Thrush – fungal infection of mouth
Importance of Fungi
1. Decomposers- recycle dead materials along with bacteria
2. Penicillin – antibiotic3. rich in vitamin C 4. Food source-5. Pest control – create competition, parasite to insects that eat crops