Physiology and Hygiene for Secondary Schools

ion is known as the trunk, and to this are attached the head, the upper extremities, and the lower extremities. These in turn present sma

he forearm, the elbow, and the upper arm are the main divisions of each of the upper extremities. The toes, the foot, the ankle, the lower leg, the knee, and the thigh are the chief divisions of each of the lower extremities. The head, wh

into [pg 005]the construction of the body. For this purpose the body of some small animal should be dissected and studied. (See observation at close of chapter.) The different materials found by such a dissection correspond closely to the substances, called tissues, which make up the human body. The main tissues of the body, as ordina

cted of wood, stone, plaster, iron, and other building materials, so is the body made up of its

king materials of the body. In serving this purpose the tissues play an active r?le. All of them must perform the activit

ssue, which is everywhere abundant, serves the general purpose of connecting the different parts together. Cartilaginous tissue forms smooth coverings over the ends of the bones and, in addition to this, supplies the necessary stiffness in organs like the larynx and the ear. The nervous tissue controls the body and brings it into proper relat

r in their properties.3 Their different properties enable them to serve different purposes in the body. Somewhat as glass is adapted by its transparency, hardness, and toughness to the use made of it in windows, the special prop

rvous tissue, irritability and conductivity. 4. Of cartilaginous tissue, stiffness and elasticity. 5. Of connective tissu

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e grouping of muscular and connecti

is known as an organ. The hand, for example, is an organ for grasping (Fig. 1). While the different organs of the body do not always contain the same tissues, and never co

ities of the body are of particular interest and importance. The three largest ones are the cranial cavity, containing the brain; the thoracic cavity, containing the heart and the

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n of the body to show its large cavit

in masticating the food, and in swallowing. The nose serves at least three distinct purposes. The mouth, the arms, the hands, the feet, the legs, the liver, the lungs, and the stomach are

which requires the combined action of the mouth, stomach, liver, intestines, and other organs. A number of organs working together for the same purpose form

s the hand, for example, grasp for itself or in order that the entire body may come into possession? Only slight study is sufficient to reveal the fact that each organ performs a wo

which it places in the mouth or of the heat from, fuel which it places on the fire, it is aided and supported by the work of all the other organs of the body-eyes, [pg 010] feet, brain, heart, etc. The hand does not and cannot

y as an organization. This term is broadly applied to a variety of combinations. An organization is properly defined as any group of individuals which, i

hings-one catching, another pitching, and so on. A manufacturing establishment which employs several workmen may also be an organization. The article manufactured provides the common purpose toward which all strive; and,

be found in a hive of bees. This is made up of the individual bees, and these, in c

practice the division of labor. That the body practices the division of labor is seen in the related work of the different organs. That it is made up of minute, but individual, parts will be shown in the chapter following. That it carries on a general work which is accompl

called tissues. The tissues are adapted, by their properties, to different purposes both in the construction of the body and in carrying on its work. The working parts of the body are ca

locate the chief extern

e found by dissecting

the most important uses of muscular tiss

Define a system. N

es of the body and the o

the hand? How does each of th

Show that a railway system, an ar

In what manner is the division of labor practiced

oofs that the body

TICA

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) whi

eg 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

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