44 STEUCTtfEAL tJNITS OF HUMAN TISSUES 



Connective tissue, then, consists of cells that manufac- 

 ture and give off a substance which, in. turn, binds to- 

 gether and supports other parts of the body. Besides the 

 Icinds mentioned, we have still other forms, named accord- 

 ing to the character of the intercellular material. Thus, 

 adipose tissue is a form of connective tissue in which the 

 thrown off matter consists of drops 

 ' ^ of oil or fat, held together by fibers 



. ''• '...f ' " (Fig. 15). 



'f, '^. ^'*^, Muscular tissue. — This tissue, to 



^ -' I i V ft ' which all our motions are due, con- 



^ ^%'V'*\* r ®^®*® °^ ^^^ whose protoplasm has 



•"„'" ^^Aff \ the power of contraction and expan- 



'< ;, * ', S ®^°^ especially well developed. It is 



^"{k h"'' '<S of two kinds and these kinds differ 



r^"^S^ ' ? "-^ ^°t^ ^'^ action and structure. 



^'*/ / ^ Striated, or voluntary muscular 

 tissue, is the name given to the kind 



w 



cells that are very long in comparison 



FiQ. 15 — ■ Adipose tissue ; .,,. .iii 



a, connective fibers ; h, With their Width and are marked with 

 °'^ ^^°'^^' transverse bands or striations. Such 



tissue forms the muscles of the legs, arms, back, etc. 

 Nonstriated or involuntary muscle tissue is the name 

 given to the form whose expansions and contraction are 

 not under our direct control. It is made up of cells 

 which are spindle shaped and without transverse stria- 

 tions. Such is the tissue which forms a part of the walls 

 of our digestive organs. 



Striated muscular tissue. An examination under the 

 microscope (see Ex. XXVII. and Fig. 16) shows such 



i ■ 



* . !• whose expansion and contraction is 



under our control. It is made up of 



