The integument also protects the body from excessive penetration of solar
radiation. Solar radiation is blocked by pigments (para 3-10) and by the layers of dead
3-19. GENERAL SENSIBILITY
Not the least of the functions of the integument is its general sensibility. As the
interface between the organism and the immediate environment, the integument is
subjected to many stimuli. A number of general sensory receptor organs are located in
the integument and the underlying subcutaneous layer. These receptor organs
continuously inform the brain of the conditions immediately surrounding the body.
These conditions include pain, temperature, light and heavy pressures, touch, and so
Section V. SUBCUTANEOUS LAYER
Between the integument proper and the investing deep fascia is the middle layer
called the subcutaneous layer.
SUB = under
CUTANEOUS = skin
In general, the subcutaneous layer is made up primarily of loose areolar FCT and fat.
The fat tends to be localized in special areas that are different in the two sexes. (In
affluent societies, there may be general obesity rather than localized fat.)
3-21. CUTANEOUS NAVL
Also found in the subcutaneous layer are the cutaneous NAVL (nerves, arteries,
veins, lymphatics). In addition, some of the sensory receptors of the nervous system
actually extend from the subcutaneous layer up into the papillae of the dermis,
immediately below the epidermis.
a. Cutaneous Capillaries. The cutaneous capillaries of the subcutaneous layer
tend to be localized at two levels. First, there is a superficial layer near the underside of
the dermis. Second, there is a deeper layer near the investing deep fascia. These two
layers of capillaries are more or less separated by the fatty tissue in the subcutaneous