CBSE Class 9 Biology Diversity in Living Organisms
Biodiversity and its Classification
All organisms are grouped on the basis of their physical characters.
Classification helps to divide organisms into groups.
Classifications of life forms are closely related to their evolution.Scientific Nomenclature
The scheme of classification include Kingdom, Phylum (for animals) / Division (for plants),Class, Order, Family, Genus and Species
Carolus Linnaeus is known as father of taxonomy.
In Binomial Nomenclature the first part of name refers to genus and second to species.
While writing a scientific name the first name is written with a capital letter and the second name with a small letter.
The Binomial nomenclature helps in uniformity of names of the various organisms.Five Kingdoms of Biodiversity
The 5 kingdom of living organisms includes Monera, Protista, Fungi, Plantae, and Animalia.
All the prokaryotes are grouped under kingdom Monera. Unicellular eukaryotes are classified under kingdom Protista.
Animalia includes multicellular heterotrophic organisms with no cell wall and Plantae are multicelluar organisms with cell wall.Cryptogams
In asexual reproduction only one parent is involved and the offspring is genetically identical to the parent.
Various modes of asexual reproduction are fission, fragmentation, regeneration, budding, spore formation, and vegetative propagation.
Vegetative propagation is easier and cheaper method of propagating plants.Phanerogams
Phanerogams possess well-differentiated reproductive tissues producing seeds.
Gymnosperms bear naked seeds whereas angiosperms have seeds enclosed in fruits.
Angiosperms are divided into monocots and dicots. Monocots have one cotyledon whereas dicots have 2 cotyledons in their seedsClassification of Animals
Animals are multicellular eukaryotes showing heterotrophic nutrition.
Levels of organization, coelom, body symmetry, notochord and number of germ layers are some of the features used in classifying animals into different phyla.
In Vertebrates, the notochord is replaced by vertebral column.Nonchordates - Acoelomates
The four nonchordate phyla that include acoelemates are porifera, coelenterata platyhelminthes, and nematoda.
Platyhelminthes or flatworms are dorsoventrally flattened, and Nematode or roundworms are pseudocoelomates.
Sponges are asymmetrical with cellular level of organization, while coelenterate are radially symmetrical.Nonchordates - Coelomates
The four nonchordate phyla that include coelomates are Annelida, Arthropoda, Mollusca, and Echinodermata.
Annelids includes segmented worms whereas, arthropods are organisms with jointed legs.
Phylum mollusca are characterized by soft bodied organisms, while echinoderms are marine animals with spiny skin.Vertebrates
There are five types of vertebrates namely, Pisces, Amphibia, Reptilia, Aves and Mammalia.
Pisces or fishes are aquatic organisms that breathe through gills whereas amphibians are found both in water and on land.
Pisces, amphibians, and reptiles are cold-blooded, whereas mammals and birds are warm-blooded organisms.