Class 11

• Living organisms were perceived differently by early man compared to inanimate matter
• Early man deified some inanimate matter and some animals and plants
• A common feature of inanimate and animate objects was the sense of awe or fear they evoked
• Description of living organisms, including human beings, began later in human history
• Societies with an anthropocentric view of biology made limited progress in biological knowledge
• Systematic and monumental description of life forms led to detailed systems of identification, nomenclature, and classification
• Recognition of similarities among living organisms horizontally and vertically humbled man and led to cultural movements for conservation of biodiversity
• Living organisms can be classified into different taxa based on characteristics
• Taxonomy involves characterisation, identification, classification, and nomenclature of organisms
• Human interest in organisms and their relationships led to the study of systematics
• Taxonomy is based on external and internal structure, cell structure, development process, and ecological information of organisms
• Biological names are generally in Latin and written in italics
• Scientific names for plants are based on the International Code for Botanical Nomenclature (ICBN)
• Scientific names for animals are based on the International Code of Zoological Nomenclature (ICZN)
• Scientific names ensure that each organism has only one name and that the name is unique
• Biological names consist of a generic name and a specific epithet in binomial nomenclature
• The first word in a biological name represents the genus and starts with a capital letter
• The second word in a biological name denotes the specific epithet and starts with a small letter
• The author's name appears after the specific epithet in an abbreviated form
• Classification is the process of grouping anything into convenient categories based on observable characters
• Taxa are scientific terms for these categories
• Taxa can indicate categories at different levels
• Characterisation, identification, classification, and nomenclature are basic processes in taxonomy
• Systematics involves the systematic arrangement of organisms
• Systematics is the branch of study that focuses on the systematic arrangement of organisms
• Linnaeus used Systema Naturae as the title of his publication
• The scope of systematics includes identification, nomenclature, and classification
• Systematics takes into account evolutionary relationships between organisms
• Taxonomic categories are part of the overall taxonomic arrangement and represent ranks or categories
• Each category is called a taxonomic category and all categories together form the taxonomic hierarchy
• Insects are an example of a taxonomic category, sharing common features like three pairs of jointed legs
• Common taxonomic categories include kingdom, phylum (or division for plants), class, order, family, genus, and species
• Species are groups of individual organisms with fundamental similarities
• Species can be distinguished from closely related species based on distinct morphological differences
• Examples of species include Mangifera indica, Solanum tuberosum (potato), and Panthera leo (lion)
• Genus comprises a group of related species with more characters in common compared to species of other genera
• Examples include potato and brinjal belonging to the genus Solanum
• Examples include the family Solanaceae with genera Solanum, Petunia, and Datura
• The family Felidae includes genera Panthera (lion, tiger, leopard) and Felis (cats)
• Lion, leopard, and tiger are species of the genus Panthera