The 3 Functions of the Skin - Protection, Experience & Policy
The skin or integumentary system is the body's biggest organ and is around 16% of a person's body weight. The skin's function is to keep our within and the outside world out (Protection). It safeguards us from heat, cold, and injury. Likewise, it is a sensory organ that informs us when things are too hot or too cold, too sharp or too close, and allows us to feel things with our fingers (Feeling).
The skin has mechanisms that assist us in cooling off and heat up. For instance, when the weather condition is cold, the blood vessels in our skin constrict to reroute blood to our vital organs to keep them warm. Goosebumps help keep us warm by forming a layer of erect hair to retain heat. When the weather condition is warm, the blood vessels broaden or dilate to send blood to the skin's surface to cool down. Sweating, another function of the skin, likewise assists in cooling us down. All of these systems are a kind of thermoregulation.
The skin consists of 3 significant areas.
3. Hypodermis or subcutaneous
The Epidermis comprises epithelial cells in 4 distinct layers over the majority of the body except for the hands and feet, which have an additional layer. The layers of the skin are:
The basal layer or Stratum Basale is the inmost layer of the Epidermis. It is a single row of epithelial cells called Keratinocytes, which are continuously dividing and sending brand-new cells up into the next layer. This layer consists of melanocytes and Merkel cells.
The next layer is the spinous layer or Stratum Spinosum. It is the thickest layer of the Epidermis, and here the keratinocytes spread out and secure to all the other keratinocytes creating a sort of patchwork quilt of oddly shaped cells. As a lot of the joins are at sharp angles, this is nicknamed the spiny layer. Melanin granules and Langerhan's cells exist in this layer.
The Stratum Granulosum or Granular layer is the next layer towards the surface. This layer is less thick than the Spiny Layer as the cells flatten out and end up being more compact. The granular layer is where fibers called keratin filaments begin to assemble, and lipids (fats) collect to prepare the layer to fulfill its safeguarding of the body. It is at this point that the cells are no longer living.
The Stratum Lucidum or transparent layer is just present on the palms of the hands and soles of the feet. It is made up of dead cells that look clear under a microscope. It provides an additional layer of protection and versatility to locations of most friction.
The Stratum Corneum is the thick, outer layer of the skin and consists of dead, keratinized corneocytes. The cells are bound together with connectors called desmosomes, and their function is to secure the much deeper layers from water and injury. The Stratum Corneum is continuously sloughing off its external cells while being replenished from below.
The Dermis is connective tissue. Connective tissue is a supporting structure. Its main parts are Collagen, Elastin, and Ground Substance.
The Dermis enhances the skin and supports and is comprised of connective tissue. It has two layers. They are not specified as in the skin but rather a continuum, from the papillary Dermis near the Epidermis to the reticular Dermis below it, merging with the subcutaneous tissue.
Layers of the Skin
The Papillary Dermis
The Reticular Dermis
The Papillary Dermis
The Papillary Dermis is the thin upper layer closest to the Epidermis. It is called the papillary Dermis since it projects papillae (nipple-like structures) into the Epidermis. This repairs the Dermis to the Epidermis, so they do not move over each other. The Papillary Dermis consists of Blood vessels that supply nutrients to and remove waste from the skin cells.
The Reticular Dermis
The Reticular Dermis is the most significant part of the Dermis, and it includes numerous structures such as hair roots, sebaceous glands, sweat glands, nerves, blood vessels, lymph vessels, muscles, and other glands. This layer provides strength and durability to the skin because of Collagen and Elastin fibers' scaffolding in a sort of syrup called Ground Compound.
The hypodermis or subcutaneous tissue
The hypodermis is the tissue that lies under the Dermis. It is mainly made of adipose tissue (fat), connective tissue, and capillary; however, several skin structures such as hair follicles, nerves, glands, and muscles reach this location. The hypodermis anchors the Dermis to the underlying fascia (layers surrounding body structures such as bones and muscles). The reticular Dermis mixes into the hypodermis rather than the two being well specified different layers.