Skin Thermoreceptors

1. Sweat glands are also known as _SUDORIFEROUS__ glands. One type, called _MEROCLINE_ glands, serve for evaporative cooling of the body, while the other type, called _APOCRINE glands, are scent glands. One place where the latter type can be found is the _AXILLARY_region.

16. Human populations living in areas of intense sunlight tend to be darker skinned because of the

In the article Skin Deep written by Nina Jablonski and George Chaplin, they discuss and look deeper into the diverse differences in skin color. Our skin color has developed over the years to be dark enough to prevent the damaging sunlight that has been harming our skin and the nutrient folate that it carries. At the same time out skin is light enough to receive vitamin D.

The basic function of sensory receptors is to respond to environmental stimuli and convert them into action potentials. The different types of receptors are: photoreceptors (respond to light), chemoreceptors (respond to chemicals), thermoreceptors (respond to temperature), pain receptors (respond to pain), and mechanoreceptors (all receptors that respond to mechanical energy, such as touch, pressure, stretch, hearing and balance).

Many people think that is it possible to achieve a “healthy tan,” but this thought has been proven wrong. Overexpose to UV-A and UV-B rays from the sun lead to premature aging of the skin, as well as the possible formation of skin cancer, know as melanoma. An appearance of a tan is actually a stage of burning and damage to the skin. Although a tan may be desirable to many, the fact remains that more people need to be educated on the dangers of the sun’s harmful rays, and the possible health complications of overexposure.

Geographical isolation in the past has caused a variation in skin color; natural selection selected specific skin pigments depending on environmental factors. Early humans who moved to Europe were introduced to a place that had less sunlight than their former place of residence. Overtime, light skin (skin with lower levels of melanin) was selected for since there were not as many UV rays that the skin needed protection from. But, what was wrong with having dark skin in Europe? How is extra melanin a disadvantage in this case? One thing to remember is that even though the sun can provide UV rays, sunlight is also a great source of natural vitamin D (Jablonski; Kirchweger). Vitamin D helps bones absorb calcium and is particularly essential for developing embryos in pregnant women. The adaptation for lighter skin was important because the skin needed to absorb as much sunlight as it could in order to receive optimal amounts of vitamin D (Kirchweger). However, too much vitamin D can be fatal. So as high amounts of melanin protected the skin from excessive UV rays in Africa, they also protected it from excessive vitamin D (Kirchweger).

It develops in the melanocytes, which are cells that produce melanin that gives the skin its pigment or color and protects tissues from ultra violet radiation. Dark skinned people have more melanin than light skinned people do. For this reason, Melanomia is more frequent in light skinned people. (“Detailed description “, 2000, P.2

Dermatitis is a general term that describes an inflammation of the skin. There are different types of dermatitis, including seborrheic dermatitis and atopic dermatitis (eczema). Although the disorder can have many causes and occur in many forms, it usually involves swollen, reddened and itchy skin. (www.umm.edu/altmed/articles/dermatitis-000048.htm)

The integumentary system is composed of the skin, its major organ, and accessory organs including hair, nails, oil and sweat glands. The system serves many purposes with its most important being that it is your body’s first line of defense against pathogens. The integumentary system has other functions including the regulation of body temperature, production of Vitamin D, providing a natural sunscreen, storing fatty tissue for energy and providing sensory input (In-class discussion). There are many pathologies that can affect the integumentary system, one of which, is Lyme disease.

The Integumentary system is defined as “an organ system consisting in the skin, hair, nails, and exocrine glands” (Integumentary System, 1999). This systems main purpose is to protect the body from the environment around it. The skin covers and protects tissues, nerves, veins, and muscles of the body. The hair and nails give extra strength in reinforcing the skin while keeping the body warm and protecting the skin from harmful UV rays. The exocrine glands of the skin include the sudoriferous glands, sebaceous glands, and the ceruminous glands. Each exocrine gland has a different function as well as location in the skin. The following text will explain the effects of melanoma on the integumentary system.

The Integumentary is a vast organ system composed of exocrine glands, hair, nails, and the most commonly known organ, the skin. As a large system, it can be susceptible to many different types of diseases, one of these diseases are called Psoriasis. This affects a large portion of the Integumentary system, the skin. Psoriasis are considered to be a widespread, common and recurring disease that can be chronic at times. Psoriasis are defined by its appearance of light silver in color, flaky, rash on many parts of the Epidermis.

A major function of melanin is to act as a defensive barrier of the skin against radiation damage. Ultraviolet light between the wavelengths 280-320nm (UV-B) causes sunburn and damages the skin on nonpigmented peoples. Exposure to this degree of light causes their skin to become dry, leathery, and wrinkled in appearance similar to that associated with aging. This can be seen in Whites living in Australia and South Africa, where ultraviolet light intensity is high because of the relative latitude or closeness to the equator.

Receptor - is a body structure that monitors changes in a controlled condition and sends input in the form of nerve impulses to the control center Control

2. Melanoma is also more common in people who live in areas with large amounts of UV

* Sensations: The cutaneous sensations like touch, pressure, vibration, pain, cold, hot, etc, are felt by the skin.