Brassica campestris Linn

(a) Common name of the plant is mustard.

(b) The first part of the name denotes the generic name and the second part is the species name of the plant.

(c) According to ICBN, all scientific names are comprised of one generic name followed by a species name, which have to be written in italics always. It is a rule of bionomial nomenclature.

(d) Linn means Linnaeus was the first to discover the plant. He identified, named and classified the plant, so credit is given to him by adding suffix 'Linn', after the scientific name $B$. campestris Linn.

The taxonomic aids are the aids which help in identification, classification and naming of a newly discovered organisms (plant or animal). It could be in the form of preserved document like herbaria or specimen kept at museums or scientific institutions. Other aids can be in the form of written document like monograph, taxonomic keys, couplets, etc.

A new organism found can be studied while comparing it with living plants and animals living in protected areas like Botanical gardens, Zoological parks, etc.

Botanical gardens helps in conservation of plants by

(i) Growing important local plant species and keeping record of them.

(ii) Growing and maintaining rare and endangered species.

(iii) Supplying seeds for different aspects of botanical research.

Whereas zoological parks also contribute in conserving biodiversity by

(i) Providing natural environment and open space to animals, i.e., wild life species.

(ii) Keeping them safe from their predators ensuring protection, food and shelter.

(iii) Providing home to different native and exotic wild animals.

(iv) Involving in the rescue of endangered species.

(v) Facilitating breeding of animals and releasing them free.

Thus, both botanical gardens and zoological parks play an important role in conservation of biodiversity.

Taxon is a scientific term used for different categories of classification. Taxonomic hierarchy is position of different taxonomic categories is ascending order, which describes the complete systematic position of any living organism. Given below is the flow diagram of taxonomic hierarchy

Taxon	Plant	Animal
Kingdom This is the highest category of classification, which includes all organism that share a set of distinguishing common characters. Phylum/Division It includes different classes having a few common characters.	Kingdom-Plantae Division is used in plants.	e.g., kingdom-Animalia. Phylum is used in animals e.g., Chordata includes classes like Pisces, Amphibia, Reptilia, Aves and Mammalia.
Class Represents organisms of related orders. Order It is an assemblage of families resembling one another in few characters. These characters are less similar as compared to characters of many genera placed in a family. Family It includes one or more genera differentiated from others related families by certain characteristic differences (both vegetative and reproductive).	Found only in flowering plants, i.e., Monocotyledoneae and dicotyledoneae. e.g., dicotyledoneae consists of order rosales polemoniales, sapindales, ranales etc. on the basis of floral characters. e.g., Order Polemoniales comprises families like Solanaceae and Convolvulaceae	Comprises of related orders i.e., classMammalia e.g., class-Mammalia includes order chiroptera, marsupialia, rodentia, cetacea, carnivora. e.g., order carnivore include families like Felidae (cats), canidae (dogs, foxes), ursidae (bears) etc.
Genus It is the first higher category above the species level. It is a group of species, which are related and have fever characters in common as compared to species. Species It is a group of individuals with similar morphological characters, which are able to interbreed and produce individuals of their own kind.	e.g., Family-Solanaceae comprises of genus Solanum. e.g., Solanum nigrum (brinjal) and Solanum tuberosum. Here nigrum and tuberosum are two species of Solanum genus.	e.g., hlidae comprises of genus Panthera (lion, tiger) and Felis (cats) e.g., The genus Panthera includes species leo (lion) and Panthera tigris (tiger).

As we move up in the taxonomic hierarchy the number of shared characters become less.

Identification of a plant is a scientific process. One has to study the general morphological characters along with its habitat, place of collection, time of flowering, etc., for identification. Several reference materials are available in the form of taxonomic keys. Professor meant to refer to these keys to help the student to identify the plant. This concept of key was introduced by Ray. Separate taxonomic keys are required for each taxonomic category. Keys are analytical in nature and are used as reference to help in identification of a newly discovered plant.

Metabolism is the sum of all synthesing (anabolic) and breaking down (catabolic) reactions. These are highly specific and enzymatically controlled reactions, which take place inside all the individual cells of unicellular or multicellular organisms.

These are infact the basis of life. These reactions help organism to grow, reproduce, maintain their steady state and respond to stimuli. It can be understood by taking example of digestion.

All organisms need nutrition in the form of food, which is digested by metabolic reactions either intracellularly or extracellularly depending upon the type of organisms. So, all reactions which help the organisms to breakdown food molecules and then assimilate them for their growth and reproduction are metabolic reactions.

Few reactions may be performed outside the cells, under controlled conditions, Chemical reactions usually involve specific set of conditions to take place. All biological reactions are highly specific, selective and are enzyme catalysed.