BIOLOGICAL CLASSIFICATION
INTRODUCTION :-
We need biological classification because :-
- Study of biological classification is important because study of one or two organisms, describe the characterstics of entire group of similar type of organisms.
- Biological classification helps in identification of organisms.
- Biological classification helps to identify the relationship between two different group of organisms.
- Biological classification provides exact position of the organisms in classification.
- Biological classification helps in knowing the evolutionary relationship between them.
EARLIER CLASSIFICATION :-
- The earlier biological classification was done by ARISTOTLE.
- He had done this classification by justifying their characters by morphological condition.
- He also classified blood into RBC and non-coloured blood.
TWO KINGDOM CLASSIFICATION :-
- This theory was proposed by CARLOUS LINNEAUS.
- The two kingdom were:
- KINGDOM PLANTAE
- ANIMAL KINGDOM
THREE KINGDOM CLASSIFICATION :-
- Three Kingdom classification was discovered by the HAECKEL.
- He included;
- PLANT KINGDOM
- ANIMAL KINGDOM
- KINGDOM PROTISTA
FOUR KINGDOM CLASSIFICATION :-
- Four Kingdom classification was discovered by COPELAND.
- He included;
- PLANT KINGDOM
- ANIMAL KINGDOM
- KINGDOM PROTISTA
- KINGDOM MONERA
FIVE KINGDOM CLASSIFICATION :-
- Five Kingdom classification was discovered by ROBERT.H.WHITTAKER.
- He included;
- PLANT KINGDOM
- ANIMAL KINGDOM
- KINGDOM PROTISTA
- KINGDOM MONERA
- KINGDOM FUNGI
- He selected these KINGDOM on the basis of following characterstics;
- structure of cell
- thallus organization (body shape)
- mode of nutrition.
- their reproduction method
- Phylogenetic relationships (evolutionary history).
SIX KINGDOM CLASSIFICATION :-
- Six Kingdom classification was discovered by CARL WOESE.
- He included;
- PLANT KINGDOM
- ANIMAL KINGDOM
- KINGDOM PROTISTA
- KINGDOM FUNGI
- EUBACTERIA
- ARCHAEBACTERIA
KINGDOM MONERA :
- Have bacteria as sole members.
- Cosmopolitan in distribution.
- Bacteria can have shapes like: Coccus (spherical), Bacillus (rod-shaped), Vibrio (comma shaped) and spirillum (spiral shaped).
- Bacteria are found almost everywhere and can be Photosynthetic autotrophs, Chemosynthetic autotrophs or Heterotrophs.
- Halophiles (salt-loving)
- Thermoacidophiles (in hot springs)
- Methanogens (in the marsh and in the gut of ruminant animals. Produce methane gas.
- Photosynthetic autotrophs like Cyanobacteria (Blue-green algae BGA). Some like Anabaena and Nostoc have specialized cells called heterocysts for nitrogen fixation.
- An algal bloom is a rich growth of blue green- algae over the surface of polluted water bodies
- An algal bloom releases neurotoxins, deplete oxygen and makes water unfit for use.
- Chemosynthetic autotrophs: Oxidize various inorganic substances like nitrates/nitrites, ammonia and use released energy for their ATP production. They help in nutrient recycling of N, P, Fe and S.
- Heterotrophic bacteria: Decomposers help in making curd, production of antibiotics, N2 fixation, and cause diseases like cholera, typhoid, tetanus and citrus canker. Reproduce mainly by fission.
- Mycoplasmas: Completely lack cell walls. Smallest living cells. Can survive without oxygen. Pathogenic in animals and plants.
ARCHAEBACTERIA:
- These bacteria are the primitive ones.
- Can be called as "GODFATHER of all Bacteria". (this one not to write in exam).
- Archaebacteria is also of several types:-
A]. HALOPHILES:
- Halophiles are the bacteria which are found in the area having high salt content like marshes and Lagoons.
- Are heterotrophic nutrition.
- Example is Halobacterium.
B]. THERMOACIDOPHILES:
- Thermoacidophiles are those bacteria which found in the area having high temperature and very low pH.
- Examples of these habitats are deep sea trenches and hot water springs
- These bacteria have rod shape structure.
- Examples of these bacteria are : Thermococcus, Thermoplasma.
C]. METHANOGENS :
- Methanogens are found in the area having high amount of Methane like marshes, intestine of cattles, paddy fields.
- Methanogens are round in shape.
- These bacteria are Chemoautotrophic.
- Example is Methanococcus.
EUBACTERIA:
- The word "EU" means true.
- Hence the word EUBACTERIA refers to the true bacteria.
- Eubacteria have cell wall which is rigid and made up of a substance called Murein or Peptidoglycan.
- Eubacteria show sometimes motile while sometimes non motile nature.
- Eubacteria possess flagellum.
- There are 3 mode of nutrition for Eubacteria:-
- Photosynthetic
- Chemosynthetic
- Mostly Heterotrophic.
CHEMOSYNTHETIC EUBACTERIA :
- These Eubacteria use inorganic molecules and convert them into organic molecules.
- Chemosynthetic Eubacteria are mostly found in areas where sunlight is unable to penetrate.
- Chemosynthetic Eubacteria helps in recycling Nitrogen, Phosphorus, Sulphur.
- Example of these Eubacteria are Nitrosomonas, Thermoacidophiles, Methanogen.
HETEROTROPHIC EUBACTERIA:
- These bacteria are Saprophytes and Parasites.
- Majority of bacteria like Bacillus Subtilis are decomposers.
- Streptomyces Griseus is another Eubacteria which is used for antibiotic production.
- Lactobacillus is also a kind of Eubacteria which helps in the curdling of milk.
- Azotobacter which is also a Eubacteria is used for Nitrogen fixing.
- Mycobacterium Tuberculosis Eubacteria causes the disease Tuberculosis.
- Xanthomonas and Axonopodis causes Citrus Canker.
CYANOBACTERIA :
- Cyanobacteria oftenly called as Blue Green Algae.
- These bacteria have chlorophyll.
- Cyanobacteria are similar to green plants and are photosynthetic autotrophs.
- Cyanobacteria are unicellular and Prokaryotes.
- The bacteria can be Colonial(NOSTOC) and Filamentous(SPIRULINA).
- Blue green algae may be marine or terrestrial algae.
- The colonies of Cyanobacteria are generally surrounded by Gelatinous Sheath.
- These forms blooms in polluted water bodies.
- Some of the Cyanobacteria have heterocysts and are able to fix nitrogen.
- Cyanobacteria is also known as OXYGENIC PHOTOTROPHS.
MYCOPLASMAS:
- Mycoplasmas are the smallest free living organisms.
- They are Prokaryotic.
- Mycoplasma can even survive without oxygen that it is Anaerobic.
- However, Mycoplasma lack Cell wall.
- These are Pathogenic.
- The bacterial disease PNEUOMONIA is caused by Mycoplasma Pneumoniae.
- The Mycoplasma are unaffected by cell wall targeting antibiotics.
- Examples of Mycoplasma is Pencillium.
#FUN FACT : MYCOPLASMA is known as JOKERS OF PLANT KINGDOM.
KINGDOM PROTISTA
- Protista are the unicellular Eukaryotes.
- Kingdom Protista have no defined boundary.
- Protista members are primarily aquatic.
- Forms a link between plants, animals and fungi.
- Chrysophytes (Has diatoms and golden algae/desmids)
- Fresh water/marine, photosynthetic, microscopic plankton.
- Chief producers in ocean.
- Protista have well-defined nucleus, and membrane bound organelles.
- Cell walls have silica which makes it indestructible and cell walls overlap to fit together like a soap box.
- Their accumulation forms ‘Diatomaceous Earth” (gritty soil)
- Used in polishing, filtration of oils and syrups.
- Protista reproduce sexually and asexually by a process involving cell fusion and zygote formation.
- PROTISTA IS FURTHER DIVIDED INTO;
- DINOFLAGELLATES
- EUGLENOIDS
- SLIME MOULDS
- CHRYSOPHYTES.
- PROTOZOANS and further the protozoans is also classified into different parts as following :
- AMOEBOID
- FLAGELLATED
- CILIATED
- SPOROZOANS
Dinoflagellates:
- Marine, photosynthetic, cell wall has stiff cellulose plates.
- Dinoflagellates have two flagella–one longitudinal and the other transverse in a furrow between wall plates.
- Dinoflagellate appear green, brown, yellow, blue or red depending on the main pigments present in their cells.
- Cell wall of Dinoflagellates is made up of cellulose(very stiff).
- Example: Gonyaulax multiples rapidly, makes the sea appear red (red tides) and produce toxins to kill marine animals.
- Humans affected by these water get prone to:-
- Lethal.
- Paralysis.
Euglenoids:
- Mostly found in stagnant fresh water. Have a protein rich layer ‘pellicle’ which makes the body flexible.
- Euglenoids has no cell wall.
- Photosynthetic in presence of sunlight but become heterotrophs if they do not get sunlight. (Mixotrophic nutrition)
- Example: Euglena
CLICK HERE TO READ THE NOTES OF CELL THE UNIT OF LIFE
Slime Moulds:
- Slime moulds are Saprophytic Protists.
- Under suitable conditions form an aggregate called plasmodium, grows on decaying twigs and leaves.
- During unfavorable conditions, plasmodium differentiates and forms fruiting bodies bearing spores at their tips.
- Spores have true walls which are extremely resistant and survive for many yearS.
- Spores get dispersed by air currents.
Protozoans:
- Are heterotrophs and live as predators or parasites.
- Protozoa has no cell wall.
- Protozoa is motile.
- Further Protozoa is classified on the basis of locomotory organs.
Amoeboid PROTOZOANS:
- Catch prey using pseudopodia .e.g., Amoeba.
- Some of them like Entamoeba are parasites.
- Amoeboid Protozoa have no cell wall.
- Marine forms have silica shells on their surface.
- Amoeboid Protozoa are found in freshwater, seawater, and moist soil.
- Amoebiasis is an infection caused by Entamoeba Histolytica.
Flagellated PROTOZOANS:
- Flagellated Protozoans are free living or Parasitic.
- have flagella which helps in locomotion.
- Flagellated Protozoans have no cell wall.
- Flagellated Protozoans are heterotrophic.
- Have one or more flagella. Cause disease like Sleeping Sickness e.g., Trypanosoma.
Ciliated PROTOZOANS:
- Ciliated Protozoans are aquatic organisms.
- Ciliated Protozoans have cilia as locomotory organs which help them in locomotion.
- Ciliated Protozoans have gullet which acts as a mouth.
- The coordinated movement of rows of cilia helps in capturing the food along with the water.
- Cytoproct is ANUS , in Ciliated Protozoans
- Example is PARAMECIUM.
SPOROZOANS :-
- Sporozoans are non-motile and have no cell wall.
- They have an infectious spore stage in their life.
- Example is Plasmodium.
KINGDOM FUNGI :
- Heterotrophic organisms.
- Non- chlorophyllous hyphae.
- The network of hyphae called mycelium.
- Hyphae which have multinucleated cytoplasm are called coenocytic hyphae.
- Cell wall is composed of chitin and polysaccharides.
- Cosmopolitan. Grow in warm and humid places
- Saprophytic, parasitic, symbiotic (Lichen and Mycorrhiza) e.g., Puccinia, (wheat rust disease), Penicillium, Yeast is a unicellular fungus.
- Reproduction can take place by vegetative means - fragmentation, fission and budding. Asexual reproduction by spores–conidia, sporangiospores or zoospores. Sexual reproduction by Oospores, ascospores and basidiospores–produced in fruiting bodies.
- Sexual cycle involves 3 steps:
- I. Plasmogamy (fusion of Protoplasms.)
- II. Karyogamy (fusion of two nuclei.)
- III. Meiosis in zygote resulting in haploid spores.
- Dikaryophase is a condition of having dikaryon in an intervening dikaryotic stage (n + n i.e., two nuclei per cell) between plasmogamy and karyogamy in fungi like ascomycetes and basidiomycetes.
- Occurs in Biosphere.
- Fungi prefers to grow in warm & humid places.
- Fungi are filamentous (exception: unicellular fungi- Yeast)
- Filamentous fungi consists of long, slender, thread like structure called Hyphae.
# GROUP OF HYPHAE : MYCELIUM.
COENOCYTIC HYPHAE : Hyphae with continuous tubes filled with multinucleated cytoplasm.
- Others have septate or cross wall in their Hyphae.
- Cell wall of fungi are Chitin and Polysaccharide.
- Fungi can live as symbionts, in association with;
- alga as Lichens
- roots of higher plants as mycorrhiza.
REPRODUCTION IN FUNGI:
Reproduction in Fungi can be done through :-
- Through vegetative propagation:
- BUDDING
- BINARY FISSION
- FRAGMENTATION
- Asexual Reproduction is done by spores called
- CONIDIA or
- SPORANGIOSPORES or
- ZOOSPORES.
- Sexual Reproduction is done by spores called
- Oospores.
- Ascospores.
- Basidiospores.
Fusion of protoplasm between two motile or non-motile gametes is called Plasmogamy.
- KINGDOM FUNGI is divided into :-
- Phycomycetes.
- Ascomycetes.
- Basidomycetes.
- Deuteromycetes.
Classes of Fungi:
Phycomycetes:
- They grow on decaying wood or as obligate parasites on plants .
- Mycelium is non-septate and coenocytic.
- Spores produced endogenously in sporangium.
- Asexual reproduction by Zoospores (motile) or Aplanospores (non-motile).
- Zygospores are formed by the fusion of gametes. e.g., Rhizopus, Albugo, Mucor.
Ascomycetes:
- Also known as ‘sac fungi’.
- Are saprophytic, decomposers, parasitic or coprophilous (growing on dung).
- Asexual spores are called conidia produced exogenously on the conidiophores.
- Sexual spores are called ascospores produced endogenously in ascus, produced inside fruiting bodies called Ascocarp.
- e.g., Aspergillus, Neurospora, Saccharomyces (Unicellular fungi), Claviceps, morels, truffles.
- Neurospora is used extensively in biochemical and genetic work.
Basidiomycetes:
- Mycelium septate and branched.
- Generally, asexual spores are not found.
- Vegetative reproduction by fragmentation.
- Sexual reproduction by the fusion of vegetative or somatic cells to form the basidium produced in basidiocarp.
- Basidium produces four basidiospores exogenously after meiosis. e.g., Agaricus (Mushroom), Ustilago (smut) and Puccinia (rust).
Deuteromycetes:
- Called as ‘Fungi Imperfecti’ as the sexual form (perfect stage) is not known for them.
- Once sexual form is discovered the member is moved to Ascomycetes or Basidiomycetes.
- Mycelium is septate and branched.
- Are saprophytic parasitic or decomposers. e.g, Alternaria, Colletotrichum, Trichoderma.
Kingdom Plantae and Animalia:
- Plants are eukaryotic, photosynthetic, multicellular organisms that contain light -harvesting pigments by which they perform photosynthesis.
- Cell wall is made of cellulose.
- Animals are eukaryotic, multicellular, non-photosynthetic organisms that are dependent on plants for nutrition.
- They have no cell wall.
VIRUSES, VIROIDS, PRIONS AND LICHENS:
A]. VIRUSES:-
- They did not find a place in biological classification.
- Not truly living.
- Non-cellular organisms which take over the machinery of host cell on entering it and become living but as such they have inert crystalline structure appear non-living. So, it is difficult to call them living or nonliving.
- Virus means venom or poisonous fluid. Pasteur gave the term ‘virus’.
- D. J. Ivanowsky found out that certain microbes caused Tobacco Mosaic Disease in tobacco plants.
- M.W. Beijerinek called fluid as ‘Contagium vivum fluidum’ as extracts of infected plants of tobacco could cause infection in healthy plants.
- W. M. Stanley showed viruses could be crystallized to form crystals of protein which are inert outside their specific host.
- Viruses are obligate parasites.
Structure of Virus:
- It is a nucleoprotein made up of a protein coat called Capsid. Capsid is made up of capsomeres arranged in helical or polyhedral-geometric forms. Have either DNA or RNA as genetic material which may be single or double stranded.
- Usually plant viruses have single stranded RNA; bacteriophages have double stranded DNA and animal viruses have single or double stranded RNA or double- stranded DNA.
- Diseases caused in humans: Mumps, Smallpox, herpes, influenza and AIDS etc. In plants, symptoms can be mosaic formation, leaf rolling and curling, yellowing and vein clearing, dwarfing and stunted growth.
VIROIDS :
- Infectious agent, free RNA (lack protein coat).
- RNA has low molecular weight.
- Causes potato spindle tuber disease.
- Discovered by T. O. Diener .
CLICK HERE TO READ THE NOTES OF CELL THE UNIT OF LIFE
PRIONS:
- Agents consisted of the abnormally folded protein.
- Causes Bovine spongiform encephalopathy (BSE) or mad cow disease in cattle and Creutzfeldt-Jakob disease (CJD) in Humans.
Lichens:
- Symbiotic association between algal component (Phycobiont) and fungal component (mycobiont).
- Algae provide food. Fungi provide shelter and absorb nutrients and water for algae.
- Good pollution indicators as they do not grow in polluted areas
TAGS :-
KINGDOM PLANTAE, KINGDOM PLANTAE, INFORMATION OF KINGDOM ANIMALIA, INFORMATION OF KINGDOM PLANTAE, IMPORTANCE OF KINGDOM ANIMALIA, IMPORTANCEE OF KINGDOM PLANTAE, WHAT IS KINGDOM ANIMALIA, WHAT IS KINGDOM PLANTAE, DEFINE LICHENS, WHAT IS LICHENS, HOW LICHENS IS USEFUL, IS LICHENS USEFUL FOR US, HOW LICHENS AFFECT OUR ENVIRONMENT, HOW LICHENS AFFECT US, DEFINE LICHENS, DEFINE KINGDOM ANIMALIA, DEFINE KINGDOM PLANTAE,EXPLAIN KINGDOM PLANTAE, EXPLAIN KINGDOM ANIMALIA IN , DIFFERENTIATE BETWEEN KINGDOM ANIMALIA AND KINGDOM PLANTAE, DESCRIBE KINGDOM ANIMALIA, DESCRIBE KINGDOM PLANTAE, SHORT NOTES ON KINGDOM ANIMALIA, SHORT NOTES ON KINGDOM PLANTAE, SHORT NOTES ON LICHENS. KINGDOM MONERA, KINGDOM PROTISTA, DEFINE DEUTEROMYCETES, EXPLAIN DEUTEROMYCETES, DESCRIBE DEUTEROMYCETES,WHAT IS DEUTEROMYCETES, WHAT IS THE MEANING OF DEUTEROMYCETES,KINGDOM FUNGI, EXPLAIN KINGDOM MONERA, EXPLAIN KINGDOM PROTISTA, EXPLAIN KINGDOM FUNGI. DIFFERENTIATE BETWEEN KINGDOM FUNGI AND KINGDOM MONERA, DIFFERENTIATE BETWEEN KINGDOM MONERA AND KINGDOM PROTISTA, DIFFERENTIATE BETWEEN KINGDOM PROTISTA AND KINGDOM FUNGI.KINGDOM PLANTAE,
