Classification of Living Organisms MCQs for NEET — Botany Questions with Answers

The NCERT defines, 'The branch of knowledge dealing with these aspects is referred to as taxonomy.' It also distinguishes taxonomy from systematics by stating 'The scope of systematics was later enlarged to include identification, nomenclature and classification. Systematics takes into account evolutionary relationships between organisms.'

The NCERT states, 'Classification is not a single step process but involves hierarchy of steps in which each step represents a rank or category. Since the category is a part of overall taxonomic arrangement, it is called the taxonomic category and all categories together constitute the taxonomic hierarchy. Each category, referred to as a unit of classification, in fact, represents a rank and is commonly termed as taxon (pl.: taxa).'

From Table 1.1, for Mango, 'Dicotyledonae' is listed under 'Class'. Similarly, for Wheat, 'Monocotyledonae' is listed under 'Class'. Therefore, they represent the Class level.

From Table 1.1, 'Musca' is listed under 'Genus' for Housefly and 'Mangifera' is listed under 'Genus' for Mango. Thus, both are genera.

The NCERT states, 'Hence, all these - 'Dogs', 'Cats', 'Mammals', 'Wheat', 'Rice', 'Plants', 'Animals', etc., are convenient categories we use to study organisms. The scientific term for these categories is taxa. Here you must recognise that taxa can indicate categories at very different levels. 'Plants' – also form a taxa. 'Wheat' is also a taxa.'

The taxonomic hierarchy in ascending order is Species, Genus, Family, Order, Class, Phylum/Division, Kingdom. Therefore, 'Order' comes immediately after 'Family' and before 'Class'.

As stated in the NCERT text: 'as we go higher from species to kingdom, the number of common characteristics goes on decreasing. Lower the taxa, more are the characteristics that the members within the taxon share.'

The NCERT text states: 'In case of plants, classes with a few similar characters are assigned to a higher category called Division.'

Looking at Table 1.1, for 'Man', the 'Biological Name' is 'Homo sapiens', and 'Homo' is listed under the 'Genus' column.

The NCERT text mentions: 'Each category, referred to as a unit of classification, in fact, represents a rank and is commonly termed as taxon (pl.: taxa).' It also says, 'These taxonomic groups/categories are distinct biological entities and not merely morphological aggregates.' Furthermore, based on characteristics, organisms are grouped into categories, and these categories are taxa. So all options are relevant to the definition of a taxon.