The types of glands included are the sweat glands, the sebaceous (fat/ oil)
glands, and the mammary glands (breasts). The ducts and secretory parts of these
glands are made of epithelial tissues. Backup or supporting tissue is of FCT.
a. Sweat Glands. Sweat glands consist of a coiled secretory portion and a
wavy duct which leads to the surface of the skin. The coiled secretory portion is located
in the dermis or deeper. Sweat glands are found everywhere on the body in association
with the skin.
b. Sebaceous Glands. Sebaceous glands produce an oily substance which
lubricates the skin and hairs. The oil keeps the skin and hairs flexible. The sebaceous
glands are usually found as a part of the walls of hair follicles and their oil flows into the
follicle. In a few places without hairs, they open directly to the skin surface.
c. Mammary Glands. In the adult human female, the mammary gland lies in
the subcutaneous layer anterior to the chest muscle (pectoralis major M.). Its function is
to nourish the newborn. A nipple is located near the center of each breast. Around
each nipple is a darkened area known as the areola. The tip of the nipple has many
small openings to allow the passage of the milk from the milk ducts. These ducts are
connected to lobes of glandular tissue located throughout the breast. Fat and fibrous
CT fill in the spaces among the lobes.
Nails are found on the ends of the digits (thumbs, fingers, and toes). Nails help
to protect the ends of these digits. Each nail bed is attached to the top of the terminal
phalanx (bone) of each digit. The nail itself is made up of cornified (hardened) outer cell
layers of the epidermis. The nails grow continuously from their roots.
3-8. SKIN COLORATION
a. The skin includes red, black, and yellow pigments. The proportion of these
pigments determine the skin color. This proportion is determined by genetics. The
absence of all pigments is called albinism. In albinism, white light is reflected and a pink
hue results from the color of the blood shining through the transparent skin.
b. These pigments are the source of hair color as well as the skin color.