Notes Ghar

 Ch-2 Biological  Classification  Biological classification is the scientific procedure of arranging organisms into groups and subgroups on the basis of their similarities and dissimilarities and placing the group in a hierarchy of categories. Importance of classification- It is not possible to study every organism. Study of one or two organism of a group gives sufficient information about the essential features of the group. It helps in identification of new organism. Classification helps in knowing the relationship amongst different groups of organisms. The organism of past cannot be studied without a proper system of classification. Classification Artificial system of classification Natural system of classification Phylogenetic system of classification Artificial system of classification - Only one or two morphological characters for grouping of organism is used. Flowering and non-flowering plants, enaima and anaima. Aristotle classification. Natural system of classification - Takes

  Ch: 1 The Living world Ernst Mayr: The “Darwin of 20th century” Biological concepts of species  Main characteristics of living:- Growth.                            (Not defining property) Reproduction                   (Not defining property) Metabolism                      (Defining property) Cellular organisation       (Defining property) Consciousness                 (Defining property) 1.Growth (irreversible,permanent) Twin character (increase in mass+ increase in number) Multicellular/Unicellular => Cell division ( vitro-culture )                  1. Indeterminate (Unlimited) - Plants                  2. Determinate (Limited) - Animals                   3. Intrinsic - Living                   4.Extrinsic- Non living   For Eg: Accretion of mountain ; Boulders ; Sand-mounds  Note:    1.Higher plants => [ Growth ; Reproduction ] Mutually exclusive  2.Unicellular organisms (amoeba;Bacteria) =>[ Growth;Reproduction] synonymous  2.Reproduction (2 Types : (i) Asexual (ii)Sexu

Outline classification of fishes by L.S berg upto order with reference to living fresh and marine fishes in India   :- L.S berg ( 1940 ) given the earliest scheme of classification in which having 7 classes of fishes as follows :- Class 1  : Pterichthys Class 2  : Coccostei (Extinct) Class 3  : Acanthodii fishes  Class 4  : Holocephali Class 5  : Diponi (Living) Class 6  : Elasmobranchii Class 7  : Telestomi fishes.                        Subclass 1  : Crossptergyii                       Subclass 2  : Actinopterygii