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Physiology and Hygiene for Secondary Schools by Francis M. Walters;A.M.
page 17 of 527 (03%)


*Observation on the Tissues.*—Examine with care the structures in the
entire leg of a chicken, squirrel, rabbit, or other small animal used for
food. Observe, first of all, the external covering, consisting of cuticle
and hair, claws, scales, or feathers, according to the specimen. These are
similar in structure, and they form the epidermis, which is one kind of
_epithelial_ tissue. With a sharp knife lay open the skin and observe that
it is attached to the parts underneath by thin, but tough, threads and
sheaths. These represent a variety of _connective_ tissue. The reddish
material which forms the greater portion of the specimen is a variety of
_muscular_ tissue, and its divisions are called muscles. With a blunt
instrument, separate the muscles, by tearing apart the connective tissue
binding them together, and find the glistening white strips of connective
tissue (tendons) which attach them to the bones. Find near the central
part of the leg a soft, white cord (a nerve) which represents one variety
of _nervous_ tissue. The bones, which may now be examined, form the
_osseous_ tissue. At the ends of the bones will be found a layer of
smooth, white material which represents one kind of _cartilaginous_
tissue. The _adipose_, or fatty, tissue, which is found under the skin and
between the other tissues, is easily recognized.

*Relation of the Tissues to the Organs.*—Observe in the specimen just
studied the relation of the different tissues to the organ as a whole
(regarding the leg as an organ), _i.e._, show how each of the tissues aids
in the work which the organ accomplishes. Show in particular how the
muscles supply the foot with motion, by tracing out the tendons that
connect them with the toes. Pull on the different tendons, noting the
effect upon the different parts of the foot.

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