The Living World Test - 36

The holotype is a specimen or illustration which is designated as the representative of a species and is used for identification of the new specimen. A lectotype is a specimen or any other material which is selected from original material as cited by the author when holotype is not available. It is used in absence/non-availability of the holotype. The paratype is the specimen/ material which does not serve as holotype/isotype/syntypes. Thus, the correct answer is option B.

• Each unit or category of classification is termed as a taxon.  It represents a rank. The basic unit of taxonomy is the species. 
• In biological classification taxonomic rank is the relative level of a group of organisms in a taxonomic hierarchy. 
• There are seven main taxonomic ranks and they are arranged as follows: Species --> Genus --> Family --> Order --> Class --> Phylum/ division --> kingdom. 
  

So the correct option is genus, family, order, class, phylum.

• Charaka Samhita is a Sanskrit text on Ayurveda. It describes ancient theories on the human body, etiology, and therapeutics for a wide range of diseases that was written by Charaka.
• Systema Naturae is the book written by Linnaeus that describes various species of animals and he is popularly known as the Father of taxonomy with his great knowledge.
• Species Plantarum is the book written by Linnaeus in 1753 which became the starting point for the nomenclature of plants, as no names are recognized prior to that.
• So the correct option is Species Plantarum.

Typological species is defined as a group of organisms that are morphologically similar irrespective of their breeding compatibility. It determines species as a static entity which can interbreed within their limit of variations and hence, is also termed as static concept. It is not accepted due to its consideration of species as a fixed entity. The biological species concept groups the members of the same species organisms that can potentially interbreed to produce fertile offspring. It is the most accepted concept due to its scientific criteria of classification that groups the individuals on the basis of their reproductive isolation which in turn maintain the morphological differences among the reproductively isolated individuals of the same habitat. Genetic species refers to the grouping of individuals of the basis of similarity and dissimilarity of their genetic material i.e. DNA; however, it needs sophisticated techniques of matching the DNA, DNA-DNA hybridization and DNA fingerprinting which are not always feasible to be performed. Thus, the correct answer is option B.

Species that belong to same period are termed as synchronic species; option A is incorrect. Two morphologically identical species that do not interbreed are referred to as sibling species; for example Drosophila pseudobscula and D. persimilis are sibling species that do not interbreed. Option B is correct. Reproductive isolation brought about by geographical isolation creates allopatric species which are now present in different geographical regions. Individuals of a population present in same geographical area are reproductively isolated by polyploidy and forms new species termed as sympatric species. This makes options C and D incorrect as they are the groups belonging to same or different geographical area and the question is about reproductive isolation within morphologically similar individuals. Thus, the correct answer is option B.

Aristotle recognized the resemblance in part of bodies among different individuals as being constant from generation to generation. He classified living things into plant, animal and human beings based on their morphological similarities and dissimilarities. Thus, option A is incorrect. 

The holotype is a specimen or illustration which is designated as a representative of a species and is used for identification of the new specimen. It is mounted on a single herbarium sheet or is preserved in other preparations. Whereas lectotype is the specimen or any other material which is selected from original material when holotype is not available. A specimen or any other material which serve as type specimen in absence of holotype, isotype, paratype or syntype is referred to as neotype. Thus, the correct answer is option A.

Nomenclature is to assign a universal scientific name to taxon based on the international rules agreed upon by ICBN/ICZN/ ICVN/ICNCP to maintain uniformity in the system. Classification is arrangement of organisms into groups on the basis of their similarities. Identification is reorganization of an unknown taxon by comparing it with already known taxa and assigning it correct rank and position in taxonomic hierarchy. Description of a plant includes listing of its taxonomic characters that represent its similarities and dissimilarities with other closely related taxa. Systematics is the branch of science that deals with study of diversity of organisms and their comparative and phylogenetic relationships. It aims at identification, nomenclature, description and classification of a taxon to provide an inventory of local, regional and continental plant resources. This makes all provided options correct.