WSU Biology 106 exam 2 with Complete Solutions

WSU Biology 106 exam 2 with Complete Solutions Fungi heterotrophs that feed by absorption Heterotrophs absorb nutrients from outside the body Roles of fungi decomposers, parasites, mutualists (symbiotic and microrizzae), early land colonizers What do fungi use to break complex molecules? Enzymes Chitin made of cellulose, make up the cell walls of fungi Hyphae continuous strands above/below ground, generate spores, colonizes soil Fungi life cycle Mycellum a collective group of hyphae Karyogamy fusion of genetic information Diploid phase following karyogamy short lived (2n) spore producing structures and (1n) spores Chytrids -found in freshwater and terrestrial habitats -decomposers, mutualistic, saprobic, or parasitic -diverged early in fungal evolution -zoospores: flagellated spores Zygomycetes fast growing bread and fruit molds, zygosporangia zygosporangia site of karyogamy and then meiosis Pilobolus aim their sporangia to the light Glomeromycetes Arbuscular mycorrhizae Mutually beneficial relationships between fungi and plant roots Mycorrhizae -"fungus roots" -delivers minerals and receives organic nutrients -increase plant productivity -strong added benefit to plants Ectomycorrhizal fungi grow in extracellular spaces of roots Endomycorrihizal fungi hyphae go through cell wall to plasma membrane Ascomycetes -produce saclike asci contained in fruiting bodies called ascocarps Ascocarps cup like structures that produce spores Basidiomycetes -Decomposers of wood -mushrooms, puffballs, shelf fungi, mycorrhizae, plant parasites Decomposers essential recycling between living and nonliving world Fungus plant symbiosis mycorrhizae Fungus animal symbiosis help break down