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Line 34: − The majority of fungal reproduction is asexual. There is three main methods by which fungi reproduce asexually:+ − 1.Sporulation followed by spore germination+ − *E.g. ''Aspergillus'' − 2. Fragmentation of hyphae+ − − 3. Budding of yeast cells − *E.g. ''Candida'' and ''Cryptococcus''
→Fungal Reproduction
=Fungal Reproduction=
=Fungal Reproduction=
Any fragment of hyphae can grow to form a new colony (if it is not too badly damaged). However, the main method of fungal reproduction is through spores which are produced in very large numbers. There are different types of spores: vegetative, asexual and sexual.
Vegetative spores can be divided into '''arthrospores''' and '''chlamydospores'''. Arthrospores are formed when septate hyphae disarticulate into seperate cells. Arthrospores are usually formed by dermatophytes. Chlamydospoes are formed by segmentation of mycelium. They are thick walled, enlarged, resting spores which contain reserve food material and can remain viable after the rest of the mycelium has died. Budding rom the ends or sides of the parent cell forms blastospores, for example, in ''Candida'' yeast infections.
Asexual spores are either '''sporangiospores''' or '''conidiospores'''. Sporangiospores are formed when the cytoplasm cleaves within a sporangium (multinucleate segment of hyphae) producing either naked '''zoospores''' which have one or more flagella and are liberated through a hole in the sporangial wall or producing '''aplanospores'''. Aplanospores are non-motile and walled which are released when the sporangial wall breaks down. Conidiospores, such as ''Aspergiullus'' can be formed directly from the mycelium, produced within a specialised fructification or can be formed externally by the abstriction of a conidiophore. Different types of conidia can be produced which differ in cell size and number and are called either microconidia (small and unicellular) or macroconidia (large and multicellular).
=Major pathogenic fungi=
=Major pathogenic fungi=