Most living object can be assigned to one of the two great categories of plants and animals but some microscopically small living objects have characteristics of both .Plants and animals have common ,to a greater or lesser extent almost all character of the living objects but there are some fundamental differences between them .These include the following ; [1] Method of feeding ; Animals take food in that is chemically complex [i.e., composed of macro molecules ]. It consists either of plant products or of animals that feed on plants .Thus , they are hetrotrophs . The complex food is reduced to simpler material by the process of digestion , and in this form it is taken up by the body .On the contrary , plants take in very simple substances as food which consists of simple molecules ,namelyCO2, from the air ,and water and mineral from the soil .In their leaves ,they combine CO2,and water to form a simple sugar , the glucose using energy of the sun to affect the change ,a process called photosynthesis .From the glucose so formed and mineral salts absorbed from the soil ,green plants make any of the substances needed for their existence .Obviosly plants are autotrophs and they do not depend on any source for their food . [2] Chlorophyll .The green color of the plants is due to the presence of compound called chlorophyll ,which is not present in animals .The chlorophyll is important in absorption of the solar energy , and its presence in animals .The chlorophyll is important in absorption of the solar energy, and its presence indicates fundamental difference between nourishing process of plant and animals .However ,fungi and most bacteria lack chlorophyll and therefore , must obtain both their nourishment and their energy from the food they consume , much as animals do .[3] Cellulose.A considerable proportion of the plant body is composed of a complex polysaccharide called cellulse .It is not present in animals . [4] Movement .Most of the animalos can move their whole body ,and are able to change place .On the contrary ,most plants cannot move their whole body , for example ,opening and closing of petals of certain flowers ,and movement of parts due to the growth .However ,microscopic plants move as freely as microscopic animals .[5] Growth .The animals grow only upto a certain age after which they donot grow till death.Their body body parts proportionately in all directions .On the contrary ,plants grow through out life and their growth is terminal ,i.e., they grow more along their length than width . [6] Organisation of body .In animals , parts are mostly placed in the body , whereas in plants , the parts are mostly placed on the surface of the body . [7] Receptors . The receptors are unique to animals ; they recieve stimuli and keep animals informed about the environmental changes , but in contrast with the animals ,the plants lack receptors . [8] Excretion . Animals remove out toxic wastes of their body but this doesnot takes place plants .
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