MICR 3220 Lecture Notes - Lecture 18: Ascocarp, Conidium, Ascospore

64 views5 pages

periwinklewasp877

30 Dec 2015

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Second example of disease - leading on from last class. Only infected cells on the leaf are the epidermal cells, hyphae cells are external to this. Conidiophores are produced after the third set of haustoria - oldest haustoria on the tips and youngest below that. Typical lesion will have about 5000 haustoria and that will end up about 5000 conidiophores. It takes the nutrition from one haustorium to produce one conidiophore. A typical colony that is not very large should produce about 200,000 conidia. This then gets to millions and 10s of millions of conidia on the plant. Conidiophores can be blown around in the air, it would be blown and land on another barley leaf. Wind and rain are both mechanisms to get around. Rain - conidia blowing around in the wind. Water droplet comes by and hits a conidia in the air (washing it out of the air).

Related Questions

Fungi Fungi are the great decomposers of the biosphere. Most plants form mycorrhizae with fungi to increase absorptive area without having to grow more roots, in this relationship fungi recieve carbohydrates from plants. Humans consume fungi, mushrooms, may use fungi as a source of drugs for blood pressure, antibiotics and immunosuppresive drugs. Fungi are used in biotechnology to produce fermetation products, and some have been very useful models to study gentics in eukaryotic cells that are unicellular such as yeasts. About one third of fungi may cause infections, mycoses, in plants, animals and humans. Fungi tolerate concentration of salt and sugar that plasmolyze bacteria in perserved foods exposed to air which contains fungal spores may germinate and may spoil food. Fungi have two body shapes, molds and yeasts. Mold are large and made of long filamentous hyphae. Hyphae form mats called mycelium ( plural is mycelia). Mycelia may extend for miles underground, making fungi the largest organism on earth. The visible portion of subterrean fungi are the fruitng bodies such as mushrooms. Yeasts are globular and unicellular. They may bud forming up 24 daughter cells from a single cell. When budding is incomplete it may produce a psuedohypa. Fungi that may exist in both body types are dimorphic fungi. In general, the yeast form of a dimorphic fungus is a pathogen, the filamentous form is not pathogenic. Examples are Histoplasmosis capsulatum (histoplasmosis) and Coccidiodes immitis (coccidioidomycosis). Fungi are saprobes, they absorb nutrients from the remains of dead plants or they lasso nematodes. Fungi may derive nutrients from a living plant utilizing haustoria which are modified hyphae that penetrate living plant tissue. Some fungi use melanin to absorb gamma rays which they convert to chemical energy. Some herbivores have fungi in thier gut microbiome to help digest plants. Zygomycota contains 1100 species and reproduces asexually through sporangiaspores, which form in a sac called a sporangium on a stalk called a sporangiaphore. An example is Nosema which is an obligate intracellular parasite in insects and honeybees. Ascomycota havd 32,000 species form haploid ascospores in sacs called ascus (asci plura) and reproduce asexually with condiospores which develop on the tips of hyphae on stalks called conidiophores. Examples are Claviceps purpurea, ergot, which grows on grain and causes abortions in cattle and hallucinations in humans. Penicillium the source of the first antibiotic discovered by Fleming in the 1940s. Saccharomyces, a facultative anaerobe, ferments sugar to produce alcohol and carbon dioxide gas and is used in baking and brewing. Neurospora was used as a model to study molecular biology, Beadle and Tatum established one gene one enzyme using this model organism.

14. Why are there more antibacterial drugs than antifungal drugs? Basidiomycota have fruiting bodies called basidiocarps. Basidiospores are dispersed by the wind and germinate in warm moist environments. An example is the pathogen Cryptococcus neoformans the leading cause of fungal meningitis

carmineantelope872

MICR 3220 Lecture Notes - Lecture 18: Ascocarp, Conidium, Ascospore

Document Summary

Get access

Related Documents

Biology 3218F/G Lecture Notes - Lecture 14: Mycelium, Senescence, Pezizales

Biology 3218F/G Lecture Notes - Lecture 32: Pentachlorophenol, Stem Rust, Telium

Biology 3218F/G Lecture Notes - Lecture 29: Soybean Rust, Cystidium, Surface Tension

Related Questions