Biological Classification

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RËPRØDÜÇTÏØÑ

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Vegetative propagation: By fragmentation, fission & budding.

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Asexual reproduction: By spores such as conidia, sporangiospores or

zoospores.

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Sexual reproduction: By oospores, ascospores and basidiospores. They

are produced in distinct structures called fruiting bodies.

THË SËXÜÅL ÇÝÇLË ÏÑVØLVËS 3 STËPS:

Plasmogamy: Fusion of protoplasm between two motile or

non-motile gametes.

Karyogamy: Fusion of two nuclei.

Meiosis: Zygote give rise to haploid spores.

THË SËXÜÅL ÇÝÇLË ÏÑVØLVËS

3 STËPS:

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When a fungus reproduces sexually, two haploid hyphae of compatible

mating types come together and fuse.

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In some fungi, the fusion of two haploid cells immediately results in

diploid cells (2n).

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In

ascomycetes

and

basidiomycetes,

a

dikaryotic

stage

or

dikaryophase (n + n, i.e. two nuclei per cell) occurs. Such a condition

is called a dikaryon. Later, parental nuclei fuse and the cells become

diploid.

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The fungi form fruiting bodies in which reduction division occurs, leading

to formation of haploid spores.

Based on morphology of mycelium, mode of spore formation & fruiting

bodies, fungi are classified into different classes:

Phycomycetes

Ascomycetes

Basidiomycetes

Deuteromycetes