RELATION OF PLANT TO ANIMAL LIFE 5 



Sulphur. This is a yellow substance which is found in large 

 deposits in Louisiana, California, the Rocky Mountains and 

 Sicily. In combination it is present in gypsum, pyrites, galena, 

 etc. It is also found in many natural waters and is generally 

 present in sufficient quantities in soils for the needs of plants. 

 In certain parts of the animal body, such as the hair and other 

 nitrogenous tissues, it occupies an important place. 



Silicon occurs in combination as sand, flint, quartz, etc. It 

 is present in most rocks and soils. Plants require this element 

 to support certain parts of their structure. The hulls and straws 

 of plant substances are often comparatively rich in this element. 



Iron. We are all familiar with this element as in combination it 

 is widely distributed. Although used in small amounts by plants 

 and animals it is nevertheless very important. It is present in 

 the blood and necessary to all cells of the animal body. 



Chlorine is most commonly found as the chloride (common 

 salt). It also occurs in combination with hydrogen, as hydro- 

 chloric acid, and in the gastric juice. 



Magnesium. This element is prevalent in most rocks and soils 

 in sufficient amounts for the plant. Many natural waters contain 

 magnesium. It is found associated as carbonate, with lime. 

 Bones and muscles contain magnesium. 



Sodium. Chloride is the commonest compound of this ele- 

 ment and is found in common salt, sea water, salt lakes and in 

 many springs and waters. It occurs in sodium nitrate and 

 sodium carbonate. As chloride, sodium is very important in 

 animal life. It is present in blood serum, lymph and urine of 

 animals. It is used a great deal in the fluids of the animal body 

 and is a source of the acid in gastric juice. 



Fluorine. This element occurs in combination with calcium. 

 It is present in some mineral waters, in bones and the enamel 

 of teeth. 



Manganese occurs in combination as manganese blend, man- 

 ganese, spar, manganite, etc. Plants use this element in small 

 amounts. 



Suggestion: Secure an exhibit of substances containing the 

 elements discussed in this section. 



