Biological classification neet full revision
Hi, students let's start the third part of biological classification, in the previous video we saw the kingdom monera go and see the first part of biological classification for a better understanding of this video, now start from kingdom Protista,
All single-cell eubacteria are placed under Protista. Eubacteria means those bacteria have a nucleus in the cytoplasm.
In the next chrysophytes, dinoflagellates, euglenoids, slime, and protozoans are placed under Protista
Let's start from
Chryophytes
Ø This group includes diatoms and golden algae [desmids ]
Ø Diatoms is a special type of algae.
Ø These are found in marine as well as freshwater environments.
Ø These are microscopic and flow with water flow heans also called plankton
Ø Most of the team are photosynthetic.
[Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration]
Ø Diatoms have the cell wall form two thin overlapping shells which fit together tightly.
Ø These walls are full fill of silica and walls are indestructible
Ø The diatoms have left behind a large amount of cell wall deposits in their habitat, this habitat is known as diatomaceous earth.
Ø Diatoms are the chief producers in the oceans, also known as the pearl of the ocean.
Ø Let's start the 1st part of Chryophytes
○ Dinoflagellates
Ø These are mostly marine and photosynthetic.
Ø They appear yellow, green, brown, or blue, etc. Depending upon pigment present in their cells
Ø The cell wall of dinoflagellates has stiff cellulose plates, this characteristic feature of dinoflagellates.
Ø Most of them have flagella; one lies longitudinally and the other is transversally in between wall plates.
Ø Some red dinoflagellates undergo rapid multiplication they make the sea appear red also known as red tides. {eg. Gonyaulax }
Ø These red tides released some toxins leads to the death of a large number of other marine water animals .i.e. Fish.
Ø Let's start the 2nd part of Chryophytes
EUGLENOIDS
Ø These are mainly found in stagnant water means in stable water.
Ø They don’t have a cell wall, they have the protein-rich layers called pellicle, which make their body flexible.
Ø They also have two flagella, one is short and the other is long.
Ø They are photosynthetic in presence of sunlight and in absence of sunlight they act like heterotrophs, these organisms are also called mixotrophic organisms.
Ø Eg. Euglena.
Ø Let's start the 3rd part Chryophytes
○ Slime moulds
Ø These are mainly saprophytic protists, which means they eat or decomposers dead organisms.
Ø Under suitable conditions they form an aggregation called plasmodium and in unfavorable conditions plasmodium divide into fruiting bodies bearing spore at their tips
Ø The spore possess true walls, they vary resistant and live for many years, and the spores are dispersed by air currents .
Ø Lets start the forth and last part of chryophytes.
Protozoans
Ø All protozoans are heterotrophs means depend upon others for food.
Ø And always lives as predators or parasites.
Ø There are four groups of protozoans
1. Amoeboid protozoans,
2. Flagellated protozoans,
3. Ciliated protozoans,
4. Sporozoans.
Ø Amoeboid protozoans
▪ These organisms live in freshwater, seawater, or moist soil.
▪ They move and capture their prey by putting Pseudopodia in amoeba.
▪ Some of them are Entamoeba is a parasite.
Ø Flagellated protozoans
Ø The members of this group are either free-living or parasitic.
Ø They have flagella.
Ø some parasites cause diseases such as sleeping sickness.
Ciliated protozoans
Ø These organisms have thousands of cilia present on their body hence they are free living ,aquatic organisms .
Ø They also have cavity that opens out side the cell surface .
Ø Ex paramoecium
Sporozoans
Ø This type of organisms are divers ,they have infected spore like stage in their life cycle .
Ø The most well known bad or notorious is plasmodium [malarial parasite ] which cause malaria .
So students we end here the kingdom protista . We start the kingdom fungi in another video so keep studying and best of luck for your exams ,, and please like and sub the video .
Let's start with the 4th part of biological classification.
In the previous video we see the kingdom Protista and their types, so please see the video of our biological classification series, now start the kingdom Fungi,
Ø The kingdom fungi constitute unique heterotrophic organisms.
Ø They show a lot of differences in morphology and habitat.
Ø Some fungi we eat in daily life, e.g. mushrooms, toadstools.
Ø But some fungi are useful and some are parasites.
Ø Most fungi are multicellular organisms.
Ø But some fungi like yeast are unicellular.
Ø Yeast is used to make bread and beer.
Ø Some fungi are used to make antibiotics, e.g. penicillium.
Ø Some fungi are parasitic means they cause diseases to plants and animals. E.g. Puccinia.
Ø We keep food under the refrigerator for preventing some harmful bacteria.
Most of the fungi are filamentous [ thin in diameter ] because they are saprophytes [they obtain food from dead organisms ] but yeast is an exception because it is unicellular.
Ø Mainly fungi consist of long, slender, third structure, called hyphae.
Ø The network of hyphae is known as mycelium.
Ø those hyphae are filled with multinucleated cytoplasm are called coenocytic hyphae.
Ø The cell wall of fungi is composed of polysaccharides and chitin.
Ø Most of the fungi are heterotrophic, they absorb organic matter from the dead body hence they are also called saprophytes.
Ø And others that depend upon living plants and animals are called parasites.
Ø They also live as symbionts with algae.
Ø Symbionts means two organisms are in a symbiosis relationship and providing benefits to each other.
Ø Reproduction in fungi takes place by vegetative reproduction means fragmentation, fission, budding.
Ø Did the asexual reproduction by spores called conidia or zoospores or sporangiospores.
Ø And also done the sexual reproduction by oospores, ascospores, basidiospores.
Ø The various spores are produced by distinct structures called fruiting bodies.
Ø sexual reproduction involves the following steps.
1. Fusion of protoplasm between two motile and non-motile gametes is called plasmogamy.
2. Fusion of two nuclei is called karyogamy.
3. Meiosis In zygote resulting in haploid spores.
Ø When two fungi are reproduced sexually then two haploid hyphae of compatible mating type [means ready for reproduction or agree for sexually reproduce] come together and get the fuse.
Ø sapIn some fungi fusion is take place immediately and result in the diploid cell [2n].
And in other fungi fusion is take place by dikaryon or diary phase.
When the cell gets divided, the chromosome is to be distributed equally among daughter cells for this the chromosome needs to be duplicated and separated.is called Dicaryophase
The fungi forms fruiting bodies in which reproduction division occurs that leading to formation of haploid spores .
Fungi is also divide in various classes,
Phycomycetes ,
Ascomycetes ,
Basidiomycetes,
deuteromycetes .
Let start from Phycomycetes ,
Members of this class found in aquatic habitats and decaying wood in moist place in dump place and etc..
Asexual reproduction take place in this class by zoospores and aplanospore.in this zoospores are motile and aplanospores are non-motile .
This spores are endogenously [developing or originating within the organisms or arising from causes within the organism] produce sporangium ,
In this class zygospore are formed by fusion of two gametes .
These gametes are sometimes isogamous or oogamous .
Isogamous means similar in morphology and oogamous means diss similar in morphology.
Some common example are mucor , rhizopus and albugo .
Ascomycetes
ascomycetes are mostly multicellular` expact yeast.
They are mostly saprophytic ,decomporses, parasitic or coprophilous .here
Ø rophytic means they eat the dead oraganisms ,parasitic means causing diseases to oraganisms , coprophilous means they grow on dung means cows weast material .
Ø Mycelium is branched and septate .
Ø The special mycelium produce asexual spore conidia is called conidiophores.
Ø Conidia on germination produce mycelium .
Ø Sexual spore are called ascocarps ,which produce endogenously in sac like asci .
Ø These asci are arrange in different type of fruiting bodies called ascocarps .
Ø Some example of are Aspergillus ,claviceps and neurospora .
Ø Neurospors are used extencvaly in biochemical and genetic work .
Ø Basidiomycetes
Ø Basidomycetes are commonly called as mushrooms , bracket fungi or puffballs .
Ø They grow in soil ,on long and tree smuts .
Ø The asexual spore are generally not found but vegetative reproduction by fragementation is common .
Ø The sex organ are absent in basidiomycetes .
Ø The basidia are arranged in fruiting bodies called basidiocarps .
Ø Some common members are Agaricus ,Ustilago and puccinia .
Ø Deuteromycetes
Ø Commonly know imperfect fungi because asexual or vegetative phase of these fungi .
Ø When the sexual forms of these fungi are discovered they where moved into classes that they rightly belong .
Ø When the linkages are established then this fungi are correctly identify and move in or out of deuteromycetes .
Ø These fungi only reproduce by asexual spores called conidia .
Ø Some members of these are saprophytic and parasitic but large number of them are decomposers of litter and help in mineral cycle .
Ø Some example of this fungi are :- Alternaria ,colletrichum and trichoderma .
So here done the kingdom fungi , in next video we cover the kingdom animalia and plantae . So please do like and sub for more videos and keep study , best of luck for exam . So by and stay tuned ….
Hi, students let's start with the 5th part of biological classification in the previous video we see the all kingdom classification, now we start with kingdom Plantae and kingdom Animalia and also end the chapter with viruses, viroids, prions, and lichens.
Now start with kingdom Plantae.
Ø Kingdom Plantae includes all plants.
Ø Mainly all of them are chlorophyll-containing organisms means they are autotrophic, but few of them are heterotrophic like a parasite and insectivorous plants.
Ø Bladderwort and venus fly trap are some examples of insectivorous plants, and Cuscuta is the parasite.
Ø The plant cell have have a eukaryotic structure with prominent chloroplast and cell wall.
Ø The large cell wall is mainly made up of cellulose.
Ø Plante includes
1. Algae
2. Bryophytes
3. Pteridophytes
4. Gymnosperms
5. Angiosperms
Ø Life cycle of plants has two distinct phases
i. Diploid sporophytic
ii. Haploid gametophytic.
Ø Both phases are alternate with each other
Ø The length of these two phases depends on they are free-living or dependent on others.
Ø It varies among different groups of plants.
Ø But the phenomenon is known as alternation of generation.
We will more discuss this kingdom in chapter 3 so make sure you subscribe for more videos of the revision series. Now start the kingdom Animalia.
Ø All heterotrophic eukaryotic organisms that are multicellular and their cells lack cell walls like animals present in the kingdom Animalia.
Ø They directly depend upon the others for food.
Ø They digest their food in the internal cavity and store it in the form of glycogen or fat.
Ø Organisms in these kingdom has holozoic nutrition
Ø Holozoic nutrition means inaction, digestion, ejaculation.
Ø These kingdoms follow a definite growth pattern that has a definite shape and size.
Ø Most of them are capable of locomotion, the sexual reproduction is done by males and females by embryological development. Other features of phyla are described in chapter
Ø 4.
Ø Now start with various, viroids, prions, and lichens.
Ø In the five-kingdom systems R.H. Whittaker does not mention single-cell organisms like viruses, viroids, prions, and lichens.
Ø That we study here.
Ø Leta's start from viruses, they are didn't find any place in classification sins they are not considered as truly living.
Ø viruses are noncellular organisms characterized by having an inert crystalline structure outside the living cell.
Ø When viruses infect a cell then they start replicating means they start to grow in the host body and start killing the host.
Ø The name virus is was given by the Dmitri lvanowsky in 1892.
Ø The name virus means venom or poisonous fluid.
Ø W.M.Sanley showed that viruses could be crystallized and crystals contains largely proteins.
Ø Virus are obligate parasites.
Ø Viruses also contain genetic material that could be either RNA or DNA
Ø No viruses contain both RNA or DNA.
Ø The genetic material of the virus is infected.
Ø In viruses that infect plants have single-stranded RNA or double stood DNA
Ø In those viruses infected animals have single or double-stranded RNA or double-stranded DNA viruses
Ø Viruses cause diseases like mumps, smallpox, herpes, and influenza, AIDS is also caused by viruses.
Ø In-plant viruses can be detected by some symptoms like mosaic formation, leaf rolling, etc…..
Ø Now we are starting with viroids.
Ø T.O.Diener discovered a new infectious agent that is similar to viruses called viroids and causes diseases like potato tuber.
Ø It was found to be free RNA but it does not have protein cote that found in viruses, hence they get the name viroids.
Ø The RNA present in viroids is present are low molecular weight.
Ø Now start the prions,
Ø In modern medicine certain infections neurological diseases were found transmitted by an agent consisting of the abnormally folded protein.
Ø Agents that are similar in size to viruses are called prions.
Ø Some diseases caused by prions are bovine spongiform, mad caw , Cr-Jacob diseases in humans.
Ø Now stared with lichens.
Ø Lichens are found in symbiotic association between algae and fungi .
Ø The algae component are called as phycobiont and fungal components are know as mycobiont .
Ø The phycobiont are autotrophic and mycobiont are heterotrophic.
Ø the algae provide food for fungi and fungi provide shelter for algae ,hence their assciotion is know as symbiotic association .
Ø lichens dose not grow in polluted areas hence, they also know as good pollution indicators .
Now the biological classification revision is end here , in next video we start the new chapter called plant kingdom and also start` the revision of Maharashtra board so if you want to join our revision journy you must need to be like and subscribe and stay tuned . And by students .
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