Biology

  Biodiversity In biodiversity, a variety of different form of organism live together and interact each other in a given area. According to Edward Wilson, biodiversity is described as combined diversity at all the levels of biological organisation. Forms of Biodiversity The most important forms of them are– (i) Genetic diversity - A single species might show high diversity at the genetic level over its distributional range. The genetic variation shown by the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might be in terms of the potency and concentration of the active chemical (reserpine) that the plant produces. India has more than 50,000 genetically different strains of rice, and 1,000 varieties of mango. (ii) Species diversity - The diversity at the species level, e.g., the Western Ghats have a greater amphibian species diversity than the Eastern Ghats. (iii) Ecological diversity - At the ecosystem l...

  Ecosystem An ecosystem is a functional unit of nature, where living organisms interact among themselves and also with the surrounding physical environment. Ecosystem varies greatly in size from a small pond to a large forest or a sea. It is divided into two basic systems - Natural ecosystems - the terrestrial - e.g. forest, grassland and desert the aquatic - e.g. pond, lake, wetland, river and estuary Man-made ecosystems - e.g. crop fields and an aquarium Ecosystem - Structure and Function Components of the environment- abiotic and biotic Interaction of biotic and abiotic components result in a physical structure. Identification and enumeration of plant and animal species of an ecosystem gives its species composition. Vertical distribution of different species occupying different levels is called stratification . For example, trees occupy top vertical strata or layer of a forest, shrubs the second and herbs and grasses occu...

  Organism A biological identity who interacts within itself and with its surrounding is called an organism. Levels of Biological Organisation There are four levels of biological organisation in ecology - organisms populations communities biomes Population A group(s) of organisms(individuals) living in a well defined geographical area, share or compete for similar resources, potentially interbreed - constitute a population. e.g. the cormorants in a wetland, rats in an abandoned dwelling, teakwood trees in a forest tract, bacteria in a culture plate and lotus plants in a pond. Population A ttributes Attributes - A population has certain attributes Birth rates and Death rates - a population has birth rates and death rates. In a population these rates refer to per capita births and deaths. For example - If in a pond there were 20 lotus plants last year and through reproduction 8 new plants are added, taking the curre...