The papillary region makes up the upper layers of the

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The Papillary Regionmakes up the upper layers of the dermis; and makes up approximately 1/5thof the thickness of the dermis.The Papillary Regioncontains thin collagen fibers and fine elastic fibers.The surface area of the Papillary Regionis greatly increased by the Dermal Papillae.
Dermal Papilla:The plural form of Dermal Papillais Dermal PapillaeThe Dermal Papillaeare small nipple shaped structures that project into the undersurface of the epidermis.All dermal papillaecontain capillary loops(blood vessels); while some contain tactile receptors known as Corpuscles of Touch(Meissner Corpuscles),nerve endings that are sensitive to the touch.Some Dermal Papillaealso contain free nerve endingsdendrites that lack any apparent structural specialization.Capillary Loops:Capillary Loopscan be found in every dermal papilla.Capillary Loopsare blood vessels that enter each and every dermal papilla in order to bring oxygen and nutrients to the dermis and epidermis.Corpuscle of Touch:Corpuscles of Touch are also known as Meissner Corpuscle.Corpuscles of Touch (Meissner Corpuscles)are tactile receptors.Corpuscles of Touch (Meissner Corpuscles)are located in some of the dermal papilla and are nerve endings that aresensitive to touch. Free Nerve Ending:Free Nerve Endingsare dendrites that are found inside of some dermal papillae that lack any apparent specialization.Different Free Never Endingsinitiate signals that give riseto the sensations of warmth, coolness, pain, tickling, and itching.
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Reticular Region:The Reticular Regionis the second layer of the dermis of the cutaneous membrane; and is connected to the hypodermis (subcutaneous layer) by fibers.The Reticular Regioncontains bundles of thick collagen fibers, scattered fibroblasts, and various wandering cells (such as macrophages).In some regions of the Reticular Regionadipose cells can be found; close to the hypodermis, in the deepest part of thelayer along with coarser elastic fibers.In the reticular region, the orientation of collagen fibers into a net like manner help the skin resists stretching.In the reticular region, between the fibers the space is occupied with blood vessels, nerves, hair follicles, sebaceous (oil) glands, and sudoriferous (sweat) glands.The combination of collagen fibers in the reticular regionprovides the skin with extensibility and elasticity.Extensibility:Extensibility is the ability of tissue to stretch; this can be observable in the cutaneous membrane around joints and inpregnancy or gross obesity.Elasticity:Elasticity is the ability of tissue to return to its original shape or form after stretching.Epidermal Ridges:Epidermal Ridgesare produced during the third month of fetal development as downwards projections from the epidermis into the dermis; forming between the dermal papilla region of the dermis and the basale stratum of the epidermis.The Epidermal ridgesare responsible for forming the linesand patterns on the surface of the palms, fingertips, soles

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