No general full fledged definition for life has been articulated since time, but lists of properties have been suggested to discern ‘the inert/non-living’ from ‘the living’ of which a an organism has to posses in order for it to be considered as a living being. These include self organization or movement, growth, reproduction, inheritance, feeding, excretion, sensitivity and adaptation. Moreover, the question of what life is takes us back to evolution, that is, for an organism to be considered living, it has to be part of the fossil record. Even so, there are living organisms which do not show some of these characteristics of life.
According to Dirk and Irwin(2004), life qualifies by a collective presence of all the above stated set of characteristics. This is not necessarily correct because there are organisms which have characteristics substantial enough to qualify them as living organisms although they may lack one or two of the latter stated characteristics, hence it would be irrational to categorise them as non-living.
All living organisms are able to move in one way or another (Cole M. 2008). Living things move in a directed and controlled way, they move of their own accord as compared to the inert which move only when pushed by external forces. Animals have special organs for movement e.g legs, wings, head etc known as locomotory organs. Plants on the other hand do not show obvious signs of voluntary movement as animals do, but as a matter of fact they do move physically and voluntarily through the different types of tropisms which result from the action of auxins in response to stimuli. The point made by Cole M. (2008) that all living things move one way or another, is not entirely correct because there are living organisms which can not move, for example, bacteria without flagella. These types of bacteria have no means of movement other than those induced onto them by external forces. Other examples of a living organism which does not experience...
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