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• Classification: Technique in which organisms of similar characteristics are grouped together. Classification is done on factors like body designs, mode of nutrition, cell structure, etc.
• Evolution: Modification of characteristics in an organism to adjust in its surrounding is called as evolution.
• Primitive organisms or lower organisms: Organisms before evolution.
• Advanced organisms or higher organisms: Organisms after evolution



• Nomenclature of organisms / Deriving scientific name:
  • Must have genus and species
  • Genus must start with capital letter
  • Species must start with small letter
  • Scientific Name must be printed in italic and written by hand with underline below genus and species

  Common name	Genus	Species	Scientific name (Printed)	Scientific name (Handwritten)
  Banyan tree	Ficus	bengalensis	Ficus bengalensis	Ficus bengalensis
  Housefly	Musca	domestica	Musca domestica	Musca domestica

• Five Kingdom Classification System:
  

  Kingdom	Characteristics	Examples
  Monera	Unicellular organisms May or may not contain a cell wall Cytoplasm contains only ribosomes Cell organelles like Nucleus, mitochondria, etc are absent Autotrophic or heterotrophic mode of nutrition	Anabaena, Blue green bacteria, etc
  Protista	Unicellular and eukaryotic organisms Cell organelles like Nucleus, mitochondria, lysosomes, etc are present Some organisms may show cilia or flagella Autotrophic or heterotrophic mode of nutrition	Amoeba, Paramecium, Euglena, etc.
  Fungi	Unicellular and multicellular eukaryotic organisms Heterotrophic mode of nutrition	Penicillium, Agaricus, etc.
  Plantae	Multicellular eukaryotic organisms Autotrophic mode of nutrition	All plants
  Animalia	Multicellular eukaryotic organisms Heterotrophic mode of nutrition	Humans, animals, birds, insects, etc.

• Kingdom Plantae:
  

  Division	Characteristics	Examples
  Thallophyta	Do not have well differentiated body (root, stems and leaves are absent) Are aquatic plants Well known as algae	Spirogyra, chara, ulva, cladophora, etc
  Bryophyta	Contain stem and leaf like structures Rhizoids are present Water is conducted by process of diffusion	Funaria, Marchantia, etc
  Pteridophyta	Contains roots, stems and leaves Vascular tissues [xylem and phloem] allows conduction of water	Marsilea, ferns, etc
  Gymnosperms	Flowers and fruits are absent Outer covering of seed is absent Evergreen, woody and perennial [Live for more than 2 years]	Pine, Deodar, Cycas, etc
  Angiosperms	Flowers and fruits are present Contains seeds Can be monocot [one cotyledon] or dicot [two cotyledon]	Jowar, Maize, Groundnut, Sunflower

• Difference between monocot and dicot plants:
  

  Monocot Plants	Dicot Plants
  Have one cotyledon	Have two cotyledon
  Roots are fibrous	Shows taproot
  Leaves shows parallel venation	Leaves shows reticulate venation
  Petals in flower are three or in multiples of three	Petals in flower are four or five or in multiples of four or five
  Example : Jowar, Maize, Wheat, Coconut,etc	Example: Pea, Gram, Groundnut, Sunflower, Water Lily, etc.

• Kingdom Animalia:
  

  Phylum	Characteristics	Examples
  Porifera	Have spongy body, attached to solid support, posses holes over body Less differentiation and division into tissue Are marine animals Well known as sponges	Euplectella, Sycon, Spongilla, etc.
  Coelenterata	Are present in various body designs Body contains cavity Live in groups or independently	Hydra, Jellyfish, Sea Anemone, etc.
  Platyhelminthes	Bilaterally symmetrical Triploblastic Body appears flattened Are free living or parasites (Live on other organism and extract nutrition from their body)	Planaria, Liver Flukes, etc.
  Nematoda	Bilaterally symmetrical Triploblastic Cylindrical body Body do not have specific organs Contains pseudocoelom (small cavity)	Hookworms, Tapeworms, Pinworms, etc.
  Annelida	Bilaterally symmetrical Triploblastic Body cavity is present Show segmentation Live in freshwater and land	Earthworm, Leeches, Redworm, etc.
  Arthropoda	Bilaterally symmetrical Open circulatory system Coelomic cavity is filled with blood Have jointed legs	Prawns, Butterfly, Housefly, Spiders, Cockroach, Bee, etc.
  Mollusca	Bilaterally symmetrical and soft body Less coelomic cavity Less segments Open circulatory system May contain shell Found in land and water	Pila, Octopus, Unio, Chiton, etc.
  Echinodermata	Contains coelomic cavity Thorny skin Contains water driven tubes (allow movement) Are marine animals	Starfish, Sea urchin, Sea cucumbers, etc.
  Protochordates	Possess notochord Notochord separates stomach from nerve chord Bilaterally symmetrical, triploblastic, have coelom	Balanoglossus, Amphioxus, Lancelet, etc.

• Kingdom Animalia- Phylum Vertebrata: Are bilaterally symmetrical, triploblastic, coelomic and segmented with different tissues and organs. Here is short explanation of classes of phylum vertebrata.
  

  Class	Characteristics	Examples
  Pisces	Streamlined body Skin is covered with scales Heart has two chambers Gills are used for breathing Are cold blooded (cannot maintain their constant body temperature with respect to surrounding) Lay eggs Body structure is made of bone or cartilage	Sea horse, Scoliodon, Rohu, etc
  Amphibia	Three chambered heart Contains mucus gland inside skin Skin and lungs are responsible for breathing Lays eggs under water Can survive on water and land	Frog, Toad, Salamander, etc
  Reptilia	Have scales on skin Breathe through lungs Cold blooded Heart is three chambered [except crocodile] Lay eggs on land	Snakes, Turtles, Lizards, Crocodiles, etc.
  Aves	Warm blooded [maintain the constant body temperature, if temperature of surrounding is changed] Have feathers and wings Breathing is done through lungs Lay eggs	Parrot, Pigeon, Ostrich, etc.
  Mammalia	Have mammary glands Skin have hairs, sweat glands and oil glands Give birth to young one [except platypus]	Humans, Cats, Dogs, Whales, etc