- The number and type of organisms present on earth is called Biodiversity.
- Different kinds of organisms represent a species.
- Around 1.7 to 1.8 billion known species are present on Earth, and constantly new species are discovered.
- Nomenclature: gives a standardised name to an organism that is accepted worldwide.
- Every organism has a Unique name. No two organisms have the same name.
- Identification deals with the accurate description of an organism.
- Scientific names are based on principles and criteria set by the International Code for Botanical Nomenclature (ICBN) (for plants) and the International Code of Zoological Nomenclature (ICZN) (for animals).
- Scientific names have two components: – the Generic name and the specific epithet
- Example: – Mango, Mangifera indica
- Mangifera– Generic name and indica– specific epithet
- Universal rules of nomenclature:
- Names are usually in Latin and written in italics, regardless of where they come from.
- The first part of the name is the genus, and the second is the specific epithet.
- When handwritten, Both words in a biological name are separately underlined or printed in italics to indicate their Latin origin.
- The genus name starts with a capital letter, and the specific epithet starts with a small letter.
- After the specific description, please write the name of the person who named it—for example, Mangifera indica Linn (Linn stands for Linnaeus).
- Classification is the process by which organisms are grouped into convenient categories based on easily observable characteristics.
- These categories are called taxa.
- Living organisms can be classified into various taxa based on their characteristics.
- The process of classification is taxonomy.
- Morden taxonomy considers the external and internal structures, cellular composition, developmental processes, and ecological information of organisms during the classification of the organism.
- Systematics (Latin: ‘systema’– systematic arrangement of organisms) deals with organisms’ identification, nomenclature and classification. It also considers the evolutionary relationships between organisms.
- Classification is a hierarchically multi-step procedure, where each step signifies a distinct rank or grouping.
- This grouping is called the taxonomic category, and all categories constitute the taxonomic hierarchy.
| Common name | Phylum/Division | Genus | Family | Order | Class | Phylum/Division |
| Man | Homo sapiens | Homo | Hominidae | Primata | Mammalia | Chordata |
| Housefly | Musca domestica | Musca | Muscidae | Diptera | Insecta | Arthropoda |
| Mango | Mangifera indica | Mangifera | Anacardiaceae | Sapindales | Dicotyledonae | Angiospermae |
| Wheat | Triticum aestivum | Triticum | Poaceae | Poales | Monocotyledonae | Angiospermae |
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