Adipose Connective Tissue
Adipose tissue is "fatty tissue." The adipose cell at
first appears star-shaped. When the cell
begins to store fat in its cytoplasm,
it enlarges, losing its star shape as
the nucleus is pushed to one side (fig. 1-7). When this
process occurs to many cells, the other cell
types are crowded out and adipose
tissue is formed. Adipose tissue is
found beneath skin, between muscles, and
around joints and various organs of the body. Adipose
tissue acts as a reservoir for
energy-producing foods; helps to reduce
body heat loss (because of its poor heat
conductivity); and serves as support for various organs
and fragile structures, such as the kidneys,
blood vessels, and nerves.
Osseous Connective Tissue
This type of tissue, known as "bone tissue," is a
dense fibrous connective tissue that forms tendons,
ligaments, cartilage, and bones (fig. 1-8).
These tissues form the supporting
framework of the body.
MUSCULAR TISSUE
Muscular tissue provides for all body movement.
Contracting muscles cause body parts to move. The
three types of muscle tissue are skeletal,
smooth, and cardiac.
Skeletal Muscle Tissue
Skeletal (voluntary) muscle fiber is striated, or
striped, and is under the control of the individual's will
(fig. 1-9). For this reason, it is often
called "voluntary" muscle tissue.
Skeletal muscle tissues are usually
attached to bones. When muscle fibers are stimulated
by an action of a nerve fiber, the fibers
contract and relax. This interaction
between muscle and nervous fibers
produces movement.
Smooth Muscle Tissue
These muscle fibers are smooth, or nonstriated,
and are not under the control of the individual's will
(fig. 1-10). For this reason, this type of
muscle tissue is called "involuntary."
Smooth muscle tissue is found in the
walls of hollow organs, such as the stomach,
intestines, blood vessels, and urinary bladder. Smooth
muscle tissues are responsible for the
movement of food through the digestive
system, constricting blood vessels, and
emptying the bladder.
Figure 1-7.-Adipose connective tissue.
Figure 1-8.-Osseous (bone) connective tissue.
Figure 1-9.-Skeletal muscle tissue.
Figure 1-10.-Smooth muscle tissue.
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