Skin is the largest and heaviest body organ of the body. It consists of three key layers; the epidermis, dermis, and hypodermis. Skin deserve to either be thin or thick. The main difference is the thickness of the epidermis and dermis, which space the top two class of skin.
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Thin skin covers many of the body and also can vary in thinness, with the thinnest skin covering the eyelids. Special skin is present on the soles of the feet and palms that the hands.
In enhancement to differing thicknesses, the skin likewise differs in what is existing in the layers. Because that example, special skin has actually no hair follicles or sebaceous glands, whereas slim skin does.
In this article, we look in ~ the differences in appearance, structure, and role of thin and also thick skin.
Thin skin covers most of the body, other than on the soles that the feet and also palms the the hands, and also contains fewer cellular layers 보다 thick skin.
The epidermis of slim skin arrays from 0.07–0.15 millimeter (mm). Thin skin deserve to vary in thickness in different parts of the body and is an especially thin across the eyelids. Slim skin is thickest top top the upper back.
Thin skin likewise contains hair follicles, sweat glands, and also sebaceous glands.
Thick skin is current on the soles that the feet and also palms that the hands. This is due to the fact that these locations receive much more friction 보다 other locations of the body, and thicker skin helps to protect from potential damage.
The epidermis of thick skin deserve to be as much as 1.5 mm. Thick skin does no contain any hair follicles or sebaceous glands. Special skin additionally contains no arrector chili muscles, which reason goosebumps.
Thick skin is thicker because of it comprise an extra class in the epidermis, called the stratum lucidum. Thick skin actually has a thinner dermis layer 보다 thin skin, but is still thicker due to the stratum lucidum layer current in the epidermis.
Appearance
Thick and also thin skin show up differently under a microscope. Slim skin consists of four class in the epidermis, while thick skin includes a 5th layer. These layers include:
Stratum basale
The stratum basale, likewise known as the stratum germinativum, is the deepest layer of the epidermis. It is the class just above the dermis.
This layer repeatedly produces brand-new skin cells. It likewise contains melanocytes, which room cells that develop skin colours and help protect the skin from sun damage.
Stratum spinosum
The stratum spinosum consists of eight come ten class of cells. World may refer to the stratum spinosum together the prickle cabinet layer since of the irregular framework of cells, which look favor spines or prickles.
Stratum granulosum
The stratum granulosum consists of 3 to 5 layers of cells. The stratum granulosum includes granules, which space rich in lipids.
Stratum lucidum
Only special skin contains the stratum lucidum layer. The stratum lucidum is a thin, transparent layer consisting of 2 to three layers the cells. It includes a protein referred to as eleidin.
Stratum corneum
The stratum corneum is the top layer the the epidermis. It is composed of 20–30 class of cells. It consists of keratin and also horny scales, which make it tougher and able to thicken right into calluses.
The stratum corneum contains dead keratinocytes, which produce defensins. Defensins space strings the amino acids that safeguard the human body from infection.
Connecting the dermis and also epidermis space structures called dermal papillae. Dermal papillae are much more prominent in special skin 보다 thin skin.
Dermal papillae rise the surface area in between the epidermis and dermis, allowing for much more oxygen, food, and waste come pass in between the layers.
| Structures | Thin skin | Thick skin |
| Dermis | Thicker dermis, can vary depending upon area the body | Thinner dermis |
| Epidermis | Thinner epidermis, varying from 0.07–0.15 mm. Epidermis has 4 layers. | Thicker epidermis, varying from 0.8–1.5 mm. Epidermis contains 5 layers. |
| Sweat glands | Contains eccrine sweat glands, and also apocrine sweat glands in the armpits and also groin | No apocrine sweat glands. Just eccrine sweat glands are current in thick skin. |
| Dermal papillae | Present | More prominent |
| Sebaceous glands | Contains sebaceous glands | No sebaceous glands |
| Hair follicles | Contains hair follicles | No hair follicles |
| Stratum lucidum | No stratum lucidum layer | Stratum lucidum class in the epidermis |
| Stratum corneum | Thin stratum corneum layer | Thick stratum corneum layer |
| Stratum granulosum | Single layer of cells | 4–5 cell thick |
| Stratum spinosum and also basale layer | Stratum spinosum is thinner | Both great are an ext prominent |
Skin in general has plenty of different functions, such together protection, sensation, and thermoregulation. Both thin and thick skin have actually properties that permit the skin to role correctly.
For example, thin skin contains hair follicles, i m sorry are necessary in producing hair to aid regulate temperature and also protect native ultraviolet radiation. Hair follicles also provide epithelial stem cells, which help repair wounds.
In addition, thin skin has sebaceous glands, which create sebum. Sebum help to lubricate the skin and also protect against infections.
Thin skin likewise contains eccrine and also apocrine sweat glands. Sweat glands assist to control body temperature by release sweat to cool the body, and also also aid to fix skin damage.
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Thick skin offers protection from damages in locations that experience more friction and also abrasion, such together the palms the the hands and the soles that the feet. Special skin likewise contains eccrine sweat glands to assist regulate human body temperature.