- The gametes are multinucleate and are called coenogametes.
- Sexual reproduction produces a diploid spore called zygospore.
- Some examples are Rhizopus stolonifer, Mucor pusillus, Pilobolus crystallinus.
- Ascomycetes include pigmented moulds, yeasts, morels, truffles, cup fungi
and powdery mildews. - The mycelium consists of septate hyphae.
- Motile structures do not occur in the life cycle.
- The common mode of asexual reproduction is through the formation of
conidia. However, in yeasts asexual reproduction occurs through budding and
fission. Oidia stage is found in some other ascomycetes. - Sexual reproduction takes place through gametangial contact.
- Fertilisation takes place in two steps plasmogamy and karyogamy.
- Karyogamy is delayed after plasmogamy and a new transitional phase called dikaryophase appears in the life cycle.
- The cells of dikaryophase are called dikaryotic cells. Each cell possesses two nuclei (n + n). Later the two nuclei fuse and the cells
become diploid. - The fungi form fruiting bodies, in which reduction division occurs, leading to formation of haploid spores.
- Some examples are yeast, Aspergillus, Penicillium, Claviceps and Neurospora.
- Basidiomycetes grow in soil on logs and in living plant bodies as parasites.
- The mycelium is septate and branched. Septa have dolipores (pores with barrel shaped outgrowths).
- Vegetative reproduction occurs by fragmentation.
- The asexual spores are not found.
- The sex organs are absent but plasmogamy is brought about by fusion of two vegetative or somatic cells of different strains or
genotypes. The resultant structure is dikaryotic which gives rise to basidium. - Karyogamy and meiosis takes place in the basidium producing four basidiospores.
- Some examples are Agaricus, Ustilago and Puccinia.
- Deuteromycetes are commonly known as imperfect fungi because only the asexual or vegetative phases of these fungi are
known. - Some members of deuteromycetes are saprophytes or parasites while a large number of them are decomposers of litter and help in
mineral cycling. - The mycelium is septate and branched.
- The deuteromycetes reproduce only by asexual spores known as conidia.
- Some examples are Trichoderma, Alternaria and Colletotrichum.
Most fungi are heterotrophic and absorb soluble organic matter from dead substrates and hence are called saprophytes. Those
fungi depend on living plants and animals are called parasites. They can also live as symbionts i.e., in association with algae as
lichens and with roots of higher plants as mycorrhiza.
KINGDOM PLANTAE
- It includes all eukaryotic chlorophyll containing organisms commonly called plants.
- A few members such as bladderwort and Venus fly trap are insectivorous while few others such as Cuscuta are parasitic.
- Kingdom Plantae includes algae, bryophytes, pteridophytes, gymnosperms and angiosperms.
- Two distinct phases are present in life cycle of plants : the diploid sporophytic phase and the haploid gametophytic phase that
alternate with each other. - These two phases follow each other rigidly but in different patterns in different plant groups. This phenomenon is called
alternation of generation.
KINGDOM ANIMALIA
- This kingdom is characterised by heterotrophic, eukaryotic organisms that are multicellular and their cells lack cell walls.
- They depend directly or indirectly on plants for food. The mode of nutrition is by ingestion of food, i.e., holozoic.
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AIPMT/NEET
AIIMS
JIPMER
Analysis of various PMTs from 2013-2017