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concept of species in zoology

 CONCEPT OF SPECIES It is already been stated that individual organisms which have many features in common and able to interbreed in natural conditions are encompassed by the term species. Species is the smallest basic unit of classification. Its proper characterization is, therefore, of vital importance for a 'Natural' scheme of classification. Identifying species on the basis of reproduction, John Ray (1693) considered all individuals produced by parents of the same types as members of the same species. Linnaeus and Some others distinguished species merely on the basis of structure. Morphological Concept of Species This is the most practical and widely used species concept to describe species since people began to classify organisms. Taxonomists use this concept mostly by default because they know most of the species on Earth only from their morphology. New species are usually named on the basis of morphological species concept; morphological descriptions are all that we need...
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Nutrition in Paramecium

Paramecium is also a unicellular organisms. It has a definite shape and food is taken in at a specific spot called oral groove. Food is moved to the oral groove by the movement of cilia which are hair-like structures that cover the entire body surface of Paramecium. 


Once the food enters the cell, it is surrounded by a food vacuole. Digestive enzymes come in contact with food vacuole and carry out the process of digestion as in case of Amoeba.
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