6 ANATOMY OF THE RABBIT 



that the low power objective is in position before: {a) A shde is 

 placed under the microscope, (b) a shde is taken from under the 

 microscope, and (c) the microscope is put away. In short, 

 always keep the low power in position when the high power is not 

 in actual use. Failure to observe this rule will result in broken 

 slides and possibly a scratched lens. Draw, or sketch, three or 

 more tangent cells of representative tissues of the first four 

 elementary groups. In drawing the cells, all three of them 

 should lie in the same focal plane, for the drawing is the student's 

 interpretation of the structure of the tissue he is studying; 

 therefore he should not attempt merely "to draw what he sees." 

 The instructor should give further directions when he supplies 

 the class with slides and posts the list of required drawings. 



A. CONNECTIVE TISSUE 



A common characteristic of connective tissue is the presence 

 of few cells and of much intercellular material, especially in 

 adults where the cells become inconspicuous. The principal 

 functions of connective tissue are those of connection and sup- 

 port. It enters into the structure and attachment of every 

 organ in the body. Martin gives an idea of the very wide 

 distribution of this tissue when he states that if all the tissues 

 of the human body except connective tissue could be dissolved 

 out, the original form of the entire body and of each organ would 

 remain. 



Some of the more common kinds of adult connective tissue 

 are : (a) White fibrous, {b) yellow elastic, (c) adipose, (d) reticu- 

 lar, (e) cartilaginous, (/) osseous, (g) dentinal, {h) lymphoid, 

 and (/) corneous tissue. 



(a) White fibrous tissue fibers are very fine, transparent, 

 and are not elastic. Fascia, periosteum, muscle sheaths, 

 tendons, hgaments are composed mostly of white fibrous tissue. 



(b) Yellow elastic tissue is very elastic and forms an impor- 

 tant portion of the ligamentum nuchae, vocal cords, arteries, 

 and respiratory tubes. 



