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A Handbook of Biology

PHÝÇØMÝÇËTËS (LØWËR FÜÑGÏ)

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They occur in aquatic habitats and on decaying wood in moist and

damp places or as obligate parasites on plants.

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The mycelium is aseptate and coenocytic.

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Asexual reproduction: By motile zoospores or by non - motile

aplanospores.

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These are endogenously produced in sporangium.

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Sexual reproduction: Zygospores are formed by fusion of two gametes.

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These gametes are isogamous (similar in morphology) or anisogamous

or oogamous (dissimilar). E.g. Mucor, Rhizopus (bread mould) and

Albugo (parasitic fungi on mustard).

ÅSÇØMÝÇËTËS (SÅÇ-FÜÑGÏ)

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They are rarely unicellular (e.g., Saccharomyces) and mostly multicellular

(e.g., Penicillium).

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Mycelium is branched and septate.

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They are saprophytic, decomposers, parasitic or coprophilous (growing

on dung).

Asexual reproduction: By conidia produced exogenously

on the special mycelium called conidiophores. Conidia

germinate to produce mycelium.

E.g. Aspergillus, Claviceps and Neurospora. Neurospora

is used in biochemical and genetic work. Morels &

truffles are edible.

Sexual reproduction: By ascospores produced

endogenously in sac like asci (sing. ascus). The asci

are arranged in different types of fruiting bodies called

ascocarps.

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Yeast (Saccharomyces cerevisiae) used to make bread

and beer is called baker’s yeast and brewer's yeast.

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