Destroyable vs. Aboriginal vs. Coelomate vs. Ocean vs. Judge vs. Flag vs. Forbear vs. Awesomely vs. Fat vs. Sonhood vs. Ricochet vs. Channel vs. Trending Comparisons. Mandate vs. Skinwalker vs. Ivermectin vs. Socialism vs. Man vs. Supersonic vs. Gazelle vs.
Health Tools. Reviewed: April 29, Medically Reviewed. Skin health is important because your skin also serves to: Keep your body temperature regulated Store supplies of water, fat, and vitamin D for the rest of the body Produce sensory input to the brain through your sense of touch Your skin weighs between six and nine pounds.
A Closer Look at Skin Layers The skin is made up of three main layers: the epidermis, the dermis, and the subcutaneous tissue. The following types of cells make up the epidermis: Basal cells are at the bottom of the epidermis and continually reproduce to form new keratinocytes. Keratinocytes or squamous cells are in the middle layer of the epidermis and produce keratin, the protein that forms the protective outer layer. Keratin also is used to produce hair and nails.
Melanocytes make melanin , the pigment that provides color to the skin. People with darker skin have melanocytes that produce more melanin. Exposure to sunlight also can increase melanin production, causing freckles or a suntan. Langerhans cells are part of the body's immune system and help fight off infection. Melanocytes migrate to the epidermis from the neural crest during embryonic development.
Melanocytes are dendritic cells. The main function of melanocytes is to produce melanin. Melanocytes and melanin in the skin are shown in figure 2. Figure 2: Melanocytes and Melanin. The two types of melanin produced by melanocytes are dark brown eumelanin and yellowish or pale red phaeomealnin. Both melanin types are formed by the oxidation of tyrosine by the enzyme tyrosinase. The production of melanin is regulated by a melanocyte-stimulating hormone.
The dendrites of the melanocytes are responsible for the transfer of melanin to the adjacent epidermal cells such as keratinocytes. Keratinocytes: Keratinocytes refer to the epidermal cells that produce keratin. Melanocytes: Melanocytes refer to the mature melanin-forming cells in the skin.
Keratinocytes: Keratinocytes are differentiated from the basal layer of the epithelium. Melanocytes: Melanocytes are differentiated from the neural crest cells. What Does Skin Do? Skin, our largest organ, has many jobs. It: protects the network of muscles, bones , nerves, blood vessels, and everything else inside our bodies forms a barrier that prevents harmful substances and germs from entering the body protects body tissues against injury helps control body temperature through sweating when we're hot and by helping keep heat in the body when we're cold Without the nerve cells in skin, people couldn't feel warmth, cold, or other sensations.
What Are the Parts of Skin? In these layers are three special types of cells: Melanocytes meh-LAH-nuh-sites make melanin , the pigment that gives skin its color. All people have roughly the same number of melanocytes; the more melanin made, the darker the skin.
Exposure to sunlight increases the production of melanin, which is why people get suntanned or freckled. Keratinocytes ker-uh-TIH-no-sites make keratin , a type of protein that's a basic component of hair, skin, and nails. Keratin in the skin's outer layer helps create a protective barrier. What Does Hair Do? The hair on our heads doesn't just look nice. It keeps us warm by preserving heat. The fine hair that covers the body provides warmth and protects the skin.
What Are the Parts of Hair? Human hair consists of: the hair shaft , the part that sticks out from the skin's surface the root , a soft thickened bulb at the base of the hair the follicle FAHL-ih-kul , a sac-like pit in the skin from which the hair grows At the bottom of the follicle is the papilla puh-PILL-uh , where the actual hair growth happens.
Each hair has three layers: the medulla meh-DULL-uh at the center, which is soft the cortex , which surrounds the medulla and is the main part of the hair the cuticle KYOO-tuh-kull , the hard outer layer that protects the shaft Hair grows by forming new cells at the base of the root.
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