80 



ECOLOGY 



Part II 



:S.P. 6WSER :■•..• 



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Fig. 5.14. The web of feeding habits among the animals of pond and lake bor- 

 ders: frogs on immature insects, snails, small fishes, crustaceans; pickerel on 

 insects, fishes; turtle on tadpoles, frogs. 



cept that a larger amount is involved and for a much longer time. Large 

 amounts of lime and other minerals are temporarily stored away in plants and 

 animals. 



Water Cycle. The internal environment of the body is completely dependent 

 upon the come and go of water. It enters the body bearing traces of iron, 

 iodine, sulfur, or salt from the external environment. It leaves the body carry- 

 ing the wastes of metabolism that are records of protoplasmic activity. Water 

 rises in vapor from the sea and land, floats in the atmosphere as clouds, con- 

 denses, falls as rain, and runs down from the highlands to the sea again. Water 

 is a traveler. Like mineral matter it is taken into plants and animals but it 



