Introduction to Kingdom Fungi. What is a fungus? A eukaryotic, heterotrophic organism devoid of...
-
Upload
rachel-washington -
Category
Documents
-
view
231 -
download
0
Transcript of Introduction to Kingdom Fungi. What is a fungus? A eukaryotic, heterotrophic organism devoid of...
Introduction to Kingdom Fungi
What is a fungus?
A eukaryotic, heterotrophic organism devoid of chlorophyll that obtains its nutrients by absorption, and reproduces by spores.
Can be multicellular or unicellular
Examples of Fungi
Mushrooms and toadstools
Moulds & mildews
Yeasts (unicellular)
Mode of nutrition
Fungi=absorptive heterotrophs release digestive enzymes into surroundings Absorb digested nutrients into cells.
Hyphae (singular, hypha)
Bodies made up of hyphae Tight mass difficult to see as separate
structures. (like the ‘mushroom’ part)
Cylindrical, branching filaments composed of a tubular cell wall filled with cytoplasm and organelles
Most fungal hyphae are 2-10 m diameter
Mycelium
Loose, branching network of hyphae under the ground.
http://www.uoguelph.ca/~gbarron/MISCELLANEOUS/hairpen.htm
How Fungi Feed
Most are saprophytes: break down dead matter Play a vital role in the recycling of nutrients.
As grown along dead matter (log), break substrate down into smaller molecules. (enzymes) Extracellular digestion.
The mycelium is the part of the fungus that is digesting material. Can be deep within a decomposing tree
branch.
Parasitic Fungi
Produce hyphae called haustoria. Can penetrate host cells without killing them. Athlete’s foot, ringworm, dandruff.
C. Myrmecophila parasitizes animals.When spore lands on ant, grows in ant’s body hyphae spread through ant’s body, digesting tissues (digesting) eventually forms the ‘sex organ’ of the fungus by growing out of ant’s body.
Symbiotic Fungi
Symbiotic fungi (mutual benefit) most trees have fungi living in close contact with roots (mycorrhiza) Fungi absorbs nutrients from soil and transfers to roots Fungi benefits by absorbing nutrients from plants
some live with algae/cyanobacteria(lichens –often seen on tree trunks)
Fungi provide algae/photosynthetic bacteria with H2O and CO2 Algae/cyanobacteriaprovides nutrients for fungi
Reproduction
Can reproduce asexually and sexually
Fragmentation
Asexual
pieces of hyphaebreak off and grow into new mycelia Spore Formation
Asexual
produced by mitosis OR
Sexual
produced by meiosis
Spores:windblown reproductive cells for dispersal to new locations produced in large numbers
Note: sexual reproduction used during unfavorable conditions
Classification
4 subgroupsZygosporefungi –eg. bread mouldsClubfungi –eg. puffballs, mushroomsImperfectfungi –eg. Penicillium, Blue cheese Sacfungi –eg. truffles, yeast
Independent Reading
Read the sections on zygospores, club fungi, sac fungi, and imperfect fungi.
Make brief notes on these groups, and in your notes make sure to: Give an example of this type of fungi BRIEFLY describe how they reproduce.
Seatwork/Homework
Page 458, #1-7, 10