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Comparative studies of natural groups of organisms

(a) They have chitin as a structural Phylum Zygomycota
carbohydrate in the cell wall. This is Fungi belonging to this phylum produce
a feature typical of animals such as asexual resting spore called zygospore,
arthropods for instance insects. which is produced when two opposite
(b) They store carbohydrates in the form mating strains come close together and
of glycogen. their haploid nuclei unite. The zygospores
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(c) They are heterotrophs. Thus, they are resistant to breakage but they are light,
cannot manufacture their own food hence they can be dispersed by wind
since they are either saprophytes or and water. The structure of zygospore
parasites. The parasitic fungi can be is capable of keeping the fungus over a
facultative or obligate. long period of dormancy. Cells within
the zygospore undergo meiosis to form
haploid spores and when released under
Similarities between fungi and plants favorable conditions they germinate to form
Similar to plants, fungi have the following a new hyphae or mycelium. This phylum
features: comprises saprophytic fungi such as Mucor

(a) Their cells have cell walls. and Rhizopus stolonifer; a common bread
(b) Some fungi have vegetative bodies mould. Zygomycetes can also reproduce
that are superficially differentiated asexually by spores born out of sporangia.
into shoot-like and root-like systems. Some zygomycetes are parasites in plants,

(c) Most fungi’s growth is restricted to insects, and animals.
apical cells.
(d) They are non-motile. General characteristics of phylum
Zygomycota
(e) They reproduce sexually by formation (a) They produce a characteristic sexual
of spores such as ascospore in yeast resting spore called zygospore.
and basidiospores in mushrooms. Some (b) They are eukaryotic organisms,
fungi reproduce asexually by producing with aseptate hyphae that have
spores such as sporangiospore. well developed branching mycelia.
(f) They lack centrioles in their cells. Aseptate means without septa or
cross walls, and are sometimes called
coenocytic.
Fungi is a heterogeneous kingdom
consisting of several phyla. However, (c) They undergo both sexual and asexual
reproduction. Sexual reproduction is
despite many ways in which fungal by conjugation; this involves fusion
organisms are distinct, the major criterion of two haploid nuclei from the two
used in grouping them into their respective mating hyphae or strains to produce
groups is their reproductive structures. zygospores. Asexual reproduction
Within the kingdom Fungi, there are three occurs via haploid spores released
phyla, namely Zygomycota, Ascomycota, from sporangia.
and Basidiomycota. (d) They are saprophytes since they feed
on dead decaying organic matter by

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