PLANT AND ANIMAL LIFE 



and changed to form the woody stem, the luxuriant 

 leaves, the nectar-laden blossoms. A lamb eating the 

 clover changes it so that it is no longer clover, nor yet 

 the gas and water from which the clover was built, 

 but the flesh and bone of the sheep. 

 Food of plants and animals. 

 The building materials, or food, 

 taken by the plant or the animal 

 are so completely changed that they 

 become a living part of it. If it 

 lives, they live as woody fibre, bone, 

 muscle, or other tissue. If it dies, 

 they too are dead, and quickly or 

 slowly decay, returning to the simple 

 chemical compounds which the plant 

 had previously utilized and which 

 thus again become available for 

 other plants and through them for 

 other animals. 



Organisms. Plants and animals 

 are called organisms,* because they 

 Fl |rowii?g er S in watef pe o a n 8 e lead a more or less independent life, 

 ^dt^^hich^Vn : during which they grow and develop. 

 (Be n rgen.) 8t red " up f d ' Most . organisms begin life compara- 

 tively small and weak. 2 They develop 

 rapidly or gradually into the size, strength and per- 

 fection of the adult. They once again become weak in 

 old age, with subsequent death and decay. This se- 

 quence of growth and decay is in marked contrast to 

 the non-living world of things, which cannot grow but 

 instead are changed by being worn away and destroyed. 



1 Literally, an organism is a living unit which possesses organs. 

 The term has, however, come to include all plants and animals. 



2 The exceptions are the microscopic plants and animals. 



