Adipose tissue is one of the many different types of connective tissue found in the human body. Connective tissue composes the dermis of the skin. Unlike the cells of the epithelial layer of the epidermis, which are crowded close together, the cells of connective tissue are scattered far apart with many fibres between them. Adipose tissue is a metabolically active tissue that stores fat and releases it in response to a variety of nervous and hormonal stimuli. It also acts as an insulator to help maintain body temperature and acts as a protective padding in certain areas. Adipose tissue is also found in bone marrow.
Research Adipose tissue
The dermal papillae are small, nipple-like protrusions of the dermis that reach into the epidermis, bringing food and oxygen to the lower layers of epidermal cells. In addition, a papilla nourishes every hair follicle. Rows of papillae protruding from the dermis into the epidermis form ridges that create patterns on the skin of the hands, feet, and body. These papillary ridges on the fingertips are responsible for fingerprints. These ridges develop sometime before birth. Not only is the pattern unique for each individual, but also it never changes except to grow larger.
Research Dermal Papillae
The dermis, or corium, is the thick, relatively soft inner most tissue of the skin. It shields and repairs injured tissues and is about four times thicker than the epidermis. The
dermis consists mainly of protein collagen, which builds scar tissue to mend cuts and abrasions. The dermis nourishes the epidermis and contains nerve endings and blood vessels, and may contain some fatty tissue. The bases of hairs are also located in the dermis. Underneath the dermis is the hypodermis, which is a fatty subcutaneous layer.
Dermostosis is ossification of the dermis.
Branches and segments of nerves, called free nerve endings, are located in the dermis. They are intricately laced through the dermis and cover the whole skin. The
free nerve endings record sensations, especially pain. They are even found in the cornea of the eye where they inform the eye of touch and pressure.
Research Free Nerve Ending
The hair follicle is a tunnel-like segment of the epidermis that extends down into the dermis. The follicle is a thin sac of epidermal tissue with a bulb at the bottom. The hair follicles produce the hair. Every hair follicle is nourished by a papilla.
Research Hair Follicle
Hair shafts grow from hair follicles situated in the dermis and hypodermis. Every hair consists of a root, the part that lies under the skin, and a shaft, the part that extends from the follicle above the skin. Hair grows on every part of the skin except the palms of the hands and soles of the feet. Hair varies in length, thickness, and colour on different parts of the body and on different people. In some parts of the body, as in the skin of the eyelids, the hairs are so short that they do not to project beyond their follicles and on the face are fine, light sensory hairs called vibrissae. In other parts of the body, as on the scalp, the hair is much longer and thicker.
Research Hair Shaft
The hypodermis is a fatty subcutaneous tissue below the dermis. This tissue is rich in fat and blood vessels. The fat cells serve as a cache of energy and are consumed when nutrients run short in the blood stream. Subcutaneous tissue also cushions the muscles, bones, and organs against shocks and shields the body from cold.
Meissner's corpuscles are egg-shaped receptors consisting of a mass of intertwined fibres. They are located between the dermis and epidermis that inform the brain exactly where the skin is touched.
Meissner's corpuscles are concentrated in the fingertips and palms, lips, and tongue, nipples, penis and clitoris.
Research Meissner's Corpuscle
Pacinian corpuscles are fast-conducting, bulb-shaped receptors located deep in the dermis. They are the largest of the skin's receptors and are believed to provide instant information about how and where we move. They are also sensitive to vibration. Pacinian corpuscles are also located in joints and tendons and in tissue that lines organs and blood vessels.
Research Pacinian Corpuscle
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