CHAPTER VII 

 MUSCLE TISSUE 



Myology is the branch of anatomy which describes 

 the muscles muscle tissue. 



Muscle tissue consists of cellular elements arranged 

 in large masses to form muscles, which are attached 

 to the bones of the body, and enter into the structure 

 of numerous organs in such a manner that by their 

 contraction they are able to perform the various 

 movements of the body and functions of contained 

 organs, whether of a voluntary or involuntary 

 nature. 



Classification. The varieties of muscles are: 

 voluntary striated, involuntary non-striated, and invol- 

 untary striated. 



Voluntary Striated. These muscles are characterized 

 by being under the control of the will, also called 

 skeletal muscles, owing to their attachment to bones 

 which they move and assist to hold in position. Each 

 muscle if examined microscopically will be seen to 

 consist of a number of fibers, bound together by white 

 fibrous tissue. Each fiber is a long, narrow cylinder. 

 It varies in length from 1 to 5 inches, and exhibits 

 cross and longitudinal striations. The composition 

 of each fiber is a number of small fibers called 

 fibrillse, surrounded by a membrane the sarcolemma, 

 and separated by a clear, transparent substance 

 called sarcoplasm, and many peripherally located 

 nuclei. The sarcoplasm represents the true muscular 

 substance. The longitudinal striations or bands seen 

 are formed by the alteration of the fibrillse and the 

 sarcoplasm, but are not quite as distinct as the crossed 



