Where is dermis located

Just as abnormal growths in the epidermis give rise to the all-too-common skin cancers, tumors can arise from the dermal layer of the skin as well. One type of tumor which begins in the dermis is called a dermatofibroma or benign fibrous histiocytoma.

It's not known what exactly causes these tumors, but they frequently occur following some form of trauma. Just as it's important to protect your epidermis from too much sun, it's important to protect your dermis as well. Sun exposure damages collagen and causes changes in elastin , which can result in premature wrinkling. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.

Gartner L. Textbook of Histology Fourth Edition. Why Do I Get Acne? TeensHealth from Nemours. American Academy of Dermatology Association. Kobielak A, Boddupally K. Junctions and inflammation in the skin. Cell Commun Adhes.

Zhang S, Duan E. Cell Transplant. Aging changes in skin. US National Library of Medicine. July A clinical and histopathological study of cases of dermatofibroma benign fibrous histiocytoma. Ann Dermatol. Key Points The dermis is divided into a papillary region and a reticular region.

The primary function of the dermis is to cushion the body from stress and strain, and to also provide: elasticity to the skin, a sense of touch, and heat. The dermis contains hair roots, sebaceous glands, sweat glands, nerves, and blood vessels.

The hypodermis lies below the dermis and contains a protective layer of fat. Key Terms the reticular layer : The deepest layer of the dermis. The Dermis Lying underneath the epidermis—the most superficial layer of our skin—is the dermis sometimes called the corium. The Reticular Layer The reticular layer serves to strengthen the skin and also provides our skin with elasticity. The dermis also contains: Nerve endings that transmit various stimuli such as pain, itch, pressure, and temperature.

Lymphatic vessels that transport immune system cells, the cells that help destroy infectious organisms that may have found their way into our body via a scratch on the skin. Specialized cells called melanocytes produce the pigment melanin. Melanocytes originate from cells in the deepest layer of the epidermis called the basal layer. The epidermis also contains Langerhans cells, which are part of the skin's immune system.

Although these cells help detect foreign substances and defend the body against infection, they also play a role in the development of skin allergies. The dermis, the skin's next layer, is a thick layer of fibrous and elastic tissue made mostly of collagen, with a small but important component of elastin that gives the skin its flexibility and strength. The dermis contains nerve endings, sweat glands and oil glands sebaceous glands , hair follicles, and blood vessels.

The nerve endings sense pain, touch, pressure, and temperature. Some areas of the skin contain more nerve endings than others. For example, the fingertips and toes contain many nerves and are extremely sensitive to touch. The sweat glands produce sweat in response to heat and stress.

Sweat is composed of water, salt, and other chemicals. As sweat evaporates off the skin, it helps cool the body. Specialized sweat glands in the armpits and the genital region apocrine sweat glands secrete a thick, oily sweat that produces a characteristic body odor when the sweat is digested by the skin bacteria in those areas. The sebaceous glands secrete sebum into hair follicles. Sebum is an oil that keeps the skin moist and soft and acts as a barrier against foreign substances.

The hair follicles produce the various types of hair found throughout the body. Hair not only contributes to a person's appearance but has a number of important physical roles, including regulating body temperature, providing protection from injury, and enhancing sensation. A portion of the follicle also contains stem cells capable of regrowing damaged epidermis.

The blood vessels of the dermis provide nutrients to the skin and help regulate body temperature. Heat makes the blood vessels enlarge dilate , allowing large amounts of blood to circulate near the skin surface, where the heat can be released. The skin also:. Your skin takes on different thickness, color, and texture all over your body. For example, your head contains more hair follicles than anywhere else. But the soles of your feet have none.

In addition, the soles of your feet and the palms of your hands are much thicker than skin on other areas of your body. Squamous cells.