The major function of the integumentary system
Integumentary system function
Langerhans cells: Langerhans cells are dendritic cells antigen-presenting immune cells of the skin and mucosa that contain large granules. For any form of armor, a breach in the protective barrier poses a danger. Among these changes are reductions in cell division, metabolic activity, blood circulation, hormonal levels, and muscle strength Figure 3. In this micrograph of a skin cross-section, you can see a Meissner corpuscle arrow , a type of touch receptor located in a dermal papilla adjacent to the basement membrane and stratum basale of the overlying epidermis. Merkel cells, seen scattered in the stratum basale, are also touch receptors. Radiological Damage Our skin also contains melanocytes that produce a pigment called melanin. This is because in a healthy individual, when all else is held equal, their body is constantly generating heat as a result of its various metabolic and physical processes. If the body becomes excessively warm due to high temperatures, vigorous activity Figure 2 ac , or a combination of the two, sweat glands will be stimulated by the sympathetic nervous system to produce large amounts of sweat, as much as 0. Sweat excreted from sweat glands also deters microbes from over-colonizing the skin surface by generating dermicidin, which has antibiotic properties. The other is the reticular layer which is the deep layer of the dermis and consists of the dense irregular connective tissue.
Excretion There are numerous secretory glands present in the skin which secrete a large range of distinct fluids. Which of the following does not directly contribute to that function?
Integumentary system facts
The stimulus for the secretion of apocrine sweat glands is adrenaline, which is a hormone carried in the blood. The hypodermis participates, passively at least, in thermoregulation since fat is a heat insulator. Vitamin D deficiency is associated with poor development of bones in children and a softening of bones in adults. These nerve fibers respond to changes in temperature or other stimuli. The epidermis does not contain blood vessels; instead, cells in the deepest layers are nourished by diffusion from blood capillaries that are present in the upper layers of the dermis. During strenuous physical activities, such as skiing a or running c , the dermal blood vessels dilate and sweat secretion increases b. Protection The skin protects the rest of the body from the basic elements of nature such as wind, water, and UV sunlight by acting as a physical, chemical, and biological barrier. Tattooing has a long history, dating back thousands of years ago. These mechanisms prevent the body from overheating. This reduced circulation can result in the skin taking on a whitish hue.
Foods rich in vitamin D are relatively scarce and so the body synthesises the majority of vitamin D itself, in the skin. When the body temperature rises, such as when exercising on a hot day, the dermal blood vessels dilate, and the sweat glands begin to secrete more sweat.
The Merkel receptor is a disk-shaped receptor located near the border between the epidermis and dermis. Other cells in the skin secrete a substance called sebum which keeps water from going out or coming in. The absence of sun exposure can lead to a lack of vitamin D in the body, leading to a condition called rickets, a painful condition in children where the bones are misshapen due to a lack of calcium, causing bowleggedness.
These layers serve to give elasticity to the integument, allowing stretching and conferring flexibility, while also resisting distortions, wrinkling, and sagging. The hypodermis acts as an energy reserve. It is separated from the dermis by the basement membrane.
Use this quiz to check your understanding and decide whether to 1 study the previous section further or 2 move on to the next section. In addition to its essential role in bone health, vitamin D is essential for general immunity against bacterial, viral, and fungal infections.
Integumentary system structure
The skin acts as a sense organ because the epidermis, dermis, and the hypodermis contain specialized sensory nerve structures that detect touch, surface temperature, and pain. The human skin consists of three major layers: the epidermis, dermis, and hypodermis. Vitamin D3 is made in the skin when 7-dehydrocholesterol reacts with ultraviolet light. Receptors can either induce a slow response to stimulation, whereby a constant activation is initiated, or a fast response, whereby activation is only initiated at the beginning and end of stimulation. Which of the following layers of skin did he have to cut into in order to bleed? Merkel cells, seen scattered in the stratum basale, are also touch receptors. Thermoregulation Body temperature is primarily regulated by an area in the brain known as the hypothalamus. This is because in a healthy individual, when all else is held equal, their body is constantly generating heat as a result of its various metabolic and physical processes. Learning Objective Identify the source of the blood supply for the integumentary system Key Takeaways Key Points The epidermis contains no blood vessels, and cells in the deepest layers are nourished by diffusion from blood capillaries present in the upper layers of the dermis. Non-keratinized cells allow water to "stay" atop the structure. Your skin plays a vital role in your body as regards the sense of touch. Practice Questions Why do people sweat excessively when exercising outside on a hot day? In addition to sweating, arterioles in the dermis dilate so that excess heat carried by the blood can dissipate through the skin and into the surrounding environment Figure 2 b. Your sweat glands increase sweat production and the heat is evaporated away cooling the skin. If the body must cool down, the body vasodilates these blood vessels.
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