Nisha"s Blog

  Island Biogeography Theory Island is any isolated habitat that is totally separated from other of its kind like oceanic island, habitat island etc. Islands as ecological systems have such salient features as simple biotas and variability. in isolation, shape, and size. Biogeography is the study of geographical distribution of species and the reasons for the pattern of distribution. Island Biogeography is the study of pattern in the distribution of species on islands which are influenced by evolutionary and ecological processes related to characteristic island like isolation and area. Mac Arthur and Wilson first published the theory of island biogeography. Island Biogeography theory also known as Mac Arthur and Wilson theory was developed to explain the species richness. Also called as equilibrium theory of island biogeography. Background: It is well established that the number of species on islands decreases as island area decreases. Probably the most obvious reason why larger areas

  What are Spices, their properties and spice yielding plants? What are Spices? Spices are aromatic compounds derived from hard parts of the plants and are used commonly in a pulverized state or crushed/powdered state. The peculiar aroma of a spice is due to the presence of a volatile oil. Volatile oils are the oils which evaporates easily when exposed in air. They bear a certain resemblance to the fixed oils, but differ from them in that they leave no greasy stain on paper, and all dissolve readily in cold alcohol. On account of the volatile nature of their flavoring constituent spices lose aroma when exposed to the air, especially after they have been grounding, that’s why spices are suggested to stored or packed in airtight containers. Some of the important spice yielding plants are:   S.No Name Family Part used          1. Piper nigrum (Black pepper) Piperaceae dried berry-like fruits      

  Historical prospective of Plant Classification ·      Taxonomy is the science that explores, describes, names, and classifies all organisms. ·      Angiosp erm s of about 300,000  species  of flowering plants is the largest and most  diverse  group within the kingdom  Plantae . Angiosperms represent approximately 80 percent of all the known green plants now living.  ·      The development of angiosperm classification has been one of the most fascinating subject. ·      A study of sequential events led to various classifications from time to time by several eminent scholars, botanists and thinkers. Plants have been known from times immemorial and remained intimately associated with human life. ·      As the number of plants known to men increased, the necessity to organize them was felt and perhaps earliest classification came into existence. ·      The knowledge of morphology, embryology, palynology, cytology, biochemistry, physiology, and phylogeny have added steps to th

          O rigin of life on earth  How did life originate ·    The only serious hypothesis entertained by scientists is that life evolved spontaneously by a process of chemosynthesis . ·     This idea of spontaneous generation from nonliving matter was first postulated by the Russian scientist A.J. Oparin and the English scientist J.B.S. Haldane. ·     According to this hypothesis over a long period of time inorganic chemicals on the surface of the earth were transformed into simple organic chemicals in shallow pools of water. These organic chemicals in turn aggregated into more complex units. Long polymers of amino acids and nucleotides could have been part of these complex microscopic structures. Ability to replicate themselves and catalyze various chemical reactions would have made these structures the most primitive living things. ·     Because RNA could store and transmit hereditary information and also catalyze some chemical reactions scientists believe that RNA rather

Economic Botany of Fennel plant (Morphology, Cultivation and Processing) Fennel Botanical name: Foeniculum vulgare            Family: Apiaceae             Common name:   Saunf Foeniculum vulgare commonly called fennel, used in traditional medicine for wide range of ailments related to digestive, endocrine, reproductive, and respiratory systems. Phytochemical studies have shown the presence of numerous valuable compounds-volatile compounds, flavonoids, phenolic compounds, fatty acids, and amino acids. Origin : The fennel plant originated in the southern Mediterranean region and through naturalization and cultivation it grows wild throughout the Northern, Eastern, and Western hemispheres, specifically in Asia, North America, and Europe. It is cultivated in fields and also grows wild. The herb was well-known to the ancient Egyptians, Romans, Indians, and Chinese. The Romans grew it for its aromatic seeds and the edible fleshy shoots are still a very common vegetable in southern Ita

  Economic Botany of Cinnamon Botanical Name: Cinnamomum vernum       Family: Lauraceae Common Name: Dalchini                                Part used: Bark The most useful part of the cinnamon tree is the outer bark which is generally used as a spice and for several natural medicinal applications. The inner bark of the cinnamon tree has more medicinal effects and it also contains more essential oil. The cinnamon bark spice is known to be available throughout the year and is most ideal to be consumed as a tea especially during winter as it has a warm and sweet taste and is also very aromatic. Sri Lankan cinnamon contributes to 70% of the world’s true cinnamon bark production. Origin: Cinnamon is indigenous to Sri Lanka. In India this tree is grown in Kerala and forests of Western ghats. Botanical Description ·        Cinnamomum verum earlier known as Cinnamomum zeylanicum is an important evergreen tree of family Lauraceae. It is also known as True Cinnmon. The name wa