Kingdom Fungi: Structure, Classification & Examples | NCERT Biology Class 11 NEET MCQ
Overview. Alexander Fleming stated the importance of Penicillium notatum while he was working on bacteria Staphylococcus. According to Alexopoulos Fungi are nucleated with non chlorophyll bearing organisms, which reproduce by both asexually and sexually and their cell walls are made up of chitin. The study of fungi is called Mycology.
Practice more MCQs: Click here to watch the full Playlist on YouTube
Table of content
- Introduction to Kingdom Fungi
- Morphology & Structure
- Nutrition in Fungi (Saprophytic, Parasitic & Symbiotic)
- Reproduction Methods (Vegetative, Asexual & Sexual)
-
Classification of Fungi :
- Phycomycetes (Algal Fungi)
- Ascomycetes (Sac Fungi)
- Basidiomycetes (Club Fungi)
- Deuteromycetes (Imperfect Fungi)
- Economic Importance of Fungi (เคเคฐ्เคฅिเค เคฎเคนเคค्เคต)
- Practice MCQs for NEET
Watch my detailed video lecture on Fungi here:"
๐White spot on mustard and Rust and Smut disease in plant are also caused by the fungi.
๐They are saprophytic in nature because they grow on dead matter of plants and animals and collect their food from these matter.
๐Fungi need warm and humid condition to grow. ๐Body of fungi is composed of long thread like structure called hyphae. The network of hyphae is called mycelium. The hyphae is coenocytic with multinucleated or septate.
Watch my detailed video lecture on Fungi here:"
๐They cannot make their own food due to lack of chlorophyll. They also act as Biofertilizer.
๐ Their cell wall is made up of Chitin and Polysaccharides.
๐ดThey reproduce vegetatively by budding, fragmentation, fission. ๐ดSexual reproduction in fungi may be isogamous, anisogamous and oogamous.
๐ดConidia or Sporangiospore or zoospore are mode of asexual reproduction.
๐ตExtra Shot of Reproduction in Fungi
Fungi reproduce asexually by special structure like rhizomorph and sclerotia. Conidia, chlamydospore, endospores, basidiospore, uredospore, ascospores, pycniospores, teleutospore are spores in fungi that are formed in favourable condition.
Watch my detailed video lecture on Fungi here:"
๐Dikaryophase
๐ดIn unfavourable condition, two same type of hyphae are come together and fuse through conjugation tube.
๐ดTheir protoplasm are fused through conjugation tube and make a single cell by the process of plasmogamy.
๐ดAt this stage, there are two nucleus in a cell therefore this stage is called Dikaryophase and nuclei are called dikaryon. ๐ดTwo nucleus in a cell is represented by n + n.
๐ดDikaryophase stage is frequently seen in member of Ascomycetes and Basidiomycetes.
๐ดNow both nuclei are fused to each other through the karyogamy and form a diploid zygote.
๐ดThis zygote divides by meiosis and form many spores in fruiting bodies.
๐Classification of fungi: Fungi are classified into four major groups on the basis of Morphology of mycelium, formation of spores and formation of fruiting bodies.
๐Phycomycetes: ๐ดMembers of this group are found in moist, damp places, dead and decaying matter.
๐ดTheir mycelium is coenocytic with many nuclei. Their network of mycelium is well developed.
๐ดThey reproduce asexually by motile and nonmotile spores called zoospores and aplanospores respectively.
Watch my detailed video lecture on Fungi here:"
๐ดThey reproduce sexually by Zygospore that are formed by fusion of the protoplasts of two gametes.
๐ดDuring fusion of gamete, a conjugation tube is formed to make the fusion of protoplast between the two cells of fungi.Therefore they are also called conjugation fungi.
๐ดWhen both gametes are morphologically similar that are involved in sexual reproduction, then reproduction is isogamous.
๐ดIn anisogamous or oogamous , both gametes are not morphologically similar.
๐ดThey have some affinities with the algae therefore called as Algal fungi.
Example: 1. Rhizopus or Bread Mould 2 .Mucor. 3. Albugo (Parasite on Mustard.)
๐Ascomycetes:
๐ดThey are also called Sac fungi and are regarded as higher fungi.
๐ดIt is the largest group of fungi including 1700 genus and 15000 species. ๐ดThey are saprotrophs , decomposers and parasites. They are also coprophilous because they may grow on cow dung.
๐ดTheir mycelium is branched and septate.
๐ดThey reproduce asexually by the conidia. These conidia are produced exogenously on special mycelium called conidiophore.
Watch my detailed video lecture on Fungi here:"
๐ดThey reproduce sexually by the specialised sexual spores called ascospores. Ascospores are formed endogenously usually eight in numbers and present within a sac-like structure called ascus. Therefore they are called ascomycetes.
๐ดThey are mostly multicellular like penicillium but some are unicellular like Saccharomyces.
For example- Aspergillus, Claviceps, Neurospora. Fusarium.
๐๐Remember- Neurospora is widely used in biochemical and genetic experiments.
๐Basidiomycetes:
๐ดThe members are commonly called mushroom or bracket fungi or puffball.
๐ดThey are found in soil or damp trees or moist places.
๐ดThey may also be present in the plant body as parasites in the form of smut and rust.
๐ดTheir mycelium is branched and septate. ๐ดAsexual mode of reproduction is unknown but they reproduce in vegetable mode by fragmentation.
Watch my detailed video lecture on Fungi here:"
๐ดInside the basidium, by meiosis basidiospores are formed. These basidiospores are arranged in the fruiting bodies called basidiocarps.
Example: 1. Agaricus or Mushroom 2. Ustilago causes smut disease 3. Puccinia causes rust disease.
๐Deuteromycetes:
๐ดThey are also called imperfect fungi because the sexual stage is not known in members of this group.
๐ดThey reproduces by asexual means mainly through conidia like Ascomycetes.
๐ดThey were grouped initially in ascomycetes but due to absence of sexual stage.
๐ดThey have been placed in different group.They are pathogenic and cause harmful diseases in humans and animals.
Watch my detailed video lecture on Fungi here:"
๐ดTheir mycelium is branched and septate.
๐ดThey are saprotrophs or parasite .They are also involved in mineral cycling in nature. Example: Alternaria, Colletotrichum, Trichoderma.
๐ตExtrashot of Fungi Characters. They are almost cosmopolitan in nature and found in soil, water, air and even in plants and animal bodies. They have a filamentous and thallus-like body structure except yeast.They are devoid of chlorophyll therefore they are not green in color.Due to lack of chlorophyll, they do not perform photosynthesis.
They exhibit a heterotrophic mode of nutrition, thus they are not capable of making their own food. They are completely dependent on other organisms for their nutrition as Parasites and saprophytes. They are saprotrophic because they derive nutrition from the dead and decaying matter.
Their cell wall is mainly composed of chitin, a kind of polysaccharides. Along with the chitin, the cell wall of some fungi also have cellulose. Some fungi prefer be to live in darkness or in the absence of light hence they are photophobic and some may live in the presence of light called photophilic.
Body of fungi is composed of a network of thread-like structures called mycelium. The mass of mycelium forms specific fungal tissue called pseudo-parenchyma. Fungi store reserve food material in the form of glycogen.Some fungi make symbiotic association with algae and root of higher plants known as lichen and mycorrhiza respectively.
๐Commercial use of Fungi
๐ดAt industrial scale, mushrooms are cultivated from fungi. Mushrooms have high nutritional value. Mushrooms are rich in vitamin B. It is regarded as a source of protein.
๐ดYeasts are used in the bread making industry. Yeast is also used in the production of wine whisky rum industries because yeast produces ethyl alcohol by fermentation.
๐ดPenicillium is enriched in protein, vitamin A, vitamin B. It is added to increase the flavour to the cheese. Penicillin was the first antibiotics that was discovered from Penicillium notatum.
๐ดAspergillus produces citric acid, Gallic acid which is used in the chemical industry. .
1. How many Statement is / are correct with respect to Fungi.
๐ Boost Your Preparation (Topic-wise Notes):
- ๐งฌ Kingdom Monera: [Click Here]
- ๐ฆ Kingdom Protista: [Click Here]
- ๐ Kingdom Fungi: [Click Here]
- ๐งช Virus, Viroids & Prions: [Click Here]
- ๐ฟ Algae (Phycology): [Click Here]
- ๐ชด Bryophytes (Amphibians of Plant Kingdom): [Click Here]
- ๐ Pteridophytes (First Vascular Plants): [Click Here]
- ๐ฒ Gymnosperms (Naked Seed Plants): [Click Here]
.
.
Comments
Post a Comment