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THE INTERNAL ENVIRONMENT OF THE BODY 



Part III 



Atlas 



Nuchal ligament 



Stieet like extension 

 of ligament 



Scapuio 



Cartilage of 

 scapula 



Humerus 



Elbow 



Radius 



Fig. 7.6. Nuchal ligament of the horse, a strap of tough, yellow elastic fibers, often 

 called whetleather, highly developed in grazing animals. 



tremely tough yellowish tissue, sometimes called whetleather, which extends 

 along the back of the neck (Fig. 7.6). In the larger arteries these nonliving 

 elastic fibers form a large part of the wall. In older animals they lose their 

 elasticity. 



Certain connective tissue cells are storage places for fat. In adipose tissue 

 or fat each cell is so filled with the fat globule that the nucleus and cytoplasm 

 are pushed into a thin rim around it (Fig. 7.7). Fat enters and leaves the 

 cell in soluble form. Fat cells border the blood vessels, often great masses 

 of them in the mesentery of the human abdomen constituting the so-called 

 fatty apron. Blubber, the fat of whales, has long been a valuable source of 

 oil; for the whale it is a great insulation against cold as well as a store of food. 

 All insects contain more or less fat, especially caterpillars and various pupae. 

 The weight of full-grown larvae of honeybees is 65 per cent fat, due to rich 

 diet and no exercise. 



Supporting Tissues 



Cartilage and bone are living tissues with cells that produce the substances 

 giving these tissues strength and rigidity. 



