Function+of+structures


 * 1) ** __Epidermis__ ** - The primary function of the epidermis is protection. Calluses forming from the stratum lucidum form calluses to reduce friction. The stratum corneum produces keratin which provides the skin its hardness and also prevent the skin from losing or gaining water. In the stratum basale, langerhans cells phagocytize mircrobes and melanin is produced to protect the skin from too much UV exposure. Tactile cells inform the brain that an object has touched the skin. Free nerve endings inform the brain about the temperature and any pain.

__**Dermis**__- The dermis contains collagen fibers that prevent the skin from being torn. The dermis also contains elastic fibers which allow movement but also maintain normal skin tension.

**__Hypodermis__**- The hypodermis consists of adipose tissue, fat, which insulates the body. Hypodermis gives a person the round shape of the body and provides padding that protects the body.

__**Hair Shaft**__- Provides support for the hair that protrudes out of the skin. Also the hair shaft absorbs heat or stands up when its cold outside, the body is touched, or the person is scared.

**__Pore__**- The pore allows sweat from the sweat glands to come into contact in the skin and regulate body temperature. The pore also allows oil from the sebaceous glands to come onto the skin to keep hair, nails, and to remove dead cells.

**__Free nerve ending__**- sends signals to the brain when the body experiences pain or feels a change in temperature

__**Sebaceous glands**__- Sebaceous secrete oil, sebum, onto the surface of the skin to lubricate the hair and the skin. The sebum also helps keep the skin and hair waterproof. Bacteria on the skin surface are either killed or weakened by the sebum.

__**Arrector Pili Muscle**__- The arrecter pili is attached to a hair follicle. When the arrecter pili muscle contracts, the hair stands erect. This usually happens when its cold outside or when a person is scared.

**__Sensory Nerve Fiber__**- Sensory nerve fibers respond to light, touch, pressure, pain, and temperature. Sensory receptors respond by initiating signal transduction and setting up graded or action potentials in the cell.

__**Eccrine Sweat Gland**__- produces a watery liquid, sweat, onto the surface of the skin. When the sweat evaporates, the body cools down.

__**Pacinian Corpuscle**__- Pacinian corpuscle are sensory receptors that sense vibrations and touch.

__**Artery**__- carries oxygenated blood towards dermal and epidermal cells

__**Veins**__- carries deoxygenated blood away from dermal and epidermal cells

**__Adipose Tissue__**- Adipose stores energy for cellular respiration. In addition, adipose tissue helps insulate the body.

**__Hair Follicle__**- the sac where hair projects from