CHAPTER VIL 



BLOOD TISSUE. 



[The tenth variety of Connective Tissue mentioned in 

 this work.] 



Blood is a tissue of mesodermic origin, and has n 

 fluid intercellular substance, known as plasma. The 

 cellular elements are many, viz. : white corpuscles, red 

 cells, and the platelets. The blood is distributed to 

 all parts of the body by means of tubes called arteries, 

 and is returned to the heart by means of the veins. 

 The capillaries are the terminals of the arteries and the 

 beginning of the veins. Their walls are very thin, and 

 admit a change of gases between the blood and the 

 tissues. 



Exercise No, 30. Obtain a drop of blood from your 

 finger. 



1. Sterilize the lance and prick the part selected. 



2. Wipe off the first drop of blood with a clean cloth 

 wet in alcohol. 



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