BIOL 226 Lecture Notes - Lecture 11: Hypha, Nephron, Plasmogamy
3 May 2018
School
Department
Course
Professor
Biol226-Ch 31
Fungi
Key traits:
o Eukaryotes
o How they obtain nutrient
o Absorptive heterotrophs
o Sexual and asexual
o Haploid, primarily
o Chitinous cell wall
Nutrients and ecology
Heterotrophs
Absorbs their food from environment
i. Secrete powerful hydrolytic enzymes
ii. Enzyme breaks down complex molecules
Ecological role of fungi:
o Decomposer
o Parasite
o Mutualistic
Common fungi body structure:
o Yeast: single cell fungi
o Filaments; multicellular
Morphology of fungi;
o Hyphae( Hypha. S):
network of tiny filaments
Consist of tubular cell walls surrounding the plasma membrane and cytoplasm of the cell
Septa hypha: (Septum .S)
o Divide hyphae into cells by cross-wall
Coenocytic hypha
o Consists of a continuous cytoplasmic mass having hundreds or thousands of nuclei
Mycelium (Mycelia .P)
o Interwoven mass hyphae
o Infiltrate material on which the fungus feeds
Specialized hyphae in Mycorrhizal fungi
Mycorrhizae
o Mutualistic relationship between plant and fungi
o Specialized hyphae for nutrient exchange
o Improve delivery of phosphate ions and other minerals to plants
o Plant supplies fungi with organic nutrients
Plasmogamy
o Heterokaryon
Haploid nuclei don't fuse right away
Some Nuclei exchange chromosome and genes
o Dikaryotic
Document Summary
Key traits: eukaryotes, how they obtain nutrient, absorptive heterotrophs, sexual and asexual, haploid, primarily, chitinous cell wall. Ecological role of fungi: decomposer, parasite, mutualistic. Common fungi body structure: yeast: single cell fungi, filaments; multicellular. Consist of tubular cell walls surrounding the plasma membrane and cytoplasm of the cell. Septa hypha: (septum . s: divide hyphae into cells by cross-wall. Coenocytic hypha: consists of a continuous cytoplasmic mass having hundreds or thousands of nuclei. Mycorrhizae: mutualistic relationship between plant and fungi, specialized hyphae for nutrient exchange. Improve delivery of phosphate ions and other minerals to plants: plant supplies fungi with organic nutrients. Some nuclei exchange chromosome and genes: dikaryotic. Haploid nuclei pair off two to one cell. Karyogamy: fusion of nuclei producing 2n zygote and other transient structures. Variability of duration : di or hetero karyotic stage. Moulds: growing filamentous fungi that produce spores by mitosis.
