Ans: The arrangement of plants into groups and sub-groups on the basis of similarities is called classification. The characters which are uses as basis of classification are called criteria of classification.
2.What are criteria of classification?
Ans: The major criteria of classification are morphology, anatomy, Palynology (study of pollen grains), Karyology (chromosome study). Embryology, Serology (chemical studies). Phytogeography (distribution), Paleontology and life histories.
3.Define specie. Give example.
Ans: A species is a group of .natural population which can interbreed freely among them and produce fertile offspring. but are reproductively isolated from all other such groups in nature. For example all the potato plants belong to single specie called Solanum mhersum.
4.What are genera? Give example.
Ans: Genera are composed of one or more similar species. For example. Solanum tuhcrsum. Solanum nigrum Onahot and Solanum melangena Itiliaigain are placed in single genera Solanum
5.Give two importance of classification.
Ans: Classification arranges the plants in different systematic
groups. It makes easy thr the botanists or taxonomist to study different plants. Classification gives phylogenetic relationships among the plants. Thus evolution of plants can be studied from classification.
6.What is Herbalist classification system?
Ans: Organized plant classification system was absent in pre-Linnaeus period. The Greeks classified plants on the basis of habits or economic importance. So their system is called Herbalist classification system.
7.Differentiate between natural and artificial classification systems.
Ans: The classification sy stem based on one or two morphological charactersfor the identification of plants is called artificial system. The classification system which is based on set of characteristics for grouping similar plants is called natural system of classification. Various plants are grouped purely on the basis of morphological similarities in this system.
8.What is Phylogenetic system? Give its examples.
Ans: The classification system which grouped plants on the basis of set of morphological characteristics and phylogenetic relations is called phylogenetic system of classification. The classification system of Engler and Prantle and classification system of Bessey are example of phylogenetic system.
9.What is modern classification system? Give its example.
Ans: Modern System: The classification system in which plants are grouped on the basis of morphological characters and modern studies like anatomy. Palynology.serology, Karyology and embryology. Phylogeography and paleontology is modern classification system. The Takhtajans classification system is an example of the modern system. of’ classification.
10.What are the Advantages of Linnaeus system?
Ans: Linnaeus was first to introduced some system of classification. It gave some basic knowledge of classification. So it was widely accepted by the taxonomists of that time. It provided a reference work. He gave clear cut concept of species. This concept is still used today.
11.What are the Disadvantage of Linnaeus system?
Ans:Linnaeus declared his system as artificial or temporary.
realized that that this system should be changed with some natural system. Linnaeus grouped some unrelated plants due to similarity in flower structure. Similarly. Linnaeus was a religious person. lie ‘opposed the concept of evolution in classification.
12.What are disadvantages of Bentham and Hooker
Ans: This system is based on natural classification system. It uses set of morphological characteristics. But this system failed to give concept of phylogenetic relationship. Therefore, it is only a modified form of Linnaeus system. Thus this system was not accepted by many taxonomists.