Question | Answer |
dermis -L- | deep to epidermis. made of outer areolar tissue and inner dense connective tissue. -contains hair follicles, oil and sweat glands, sensory receptors, nerve fibers, blood vessels and lympathic vessels |
Cells of dermis | firbroblasts, macrophagesm, mast cells and blood cells |
layers of dermis -L- | papillary layer and reticular layer |
papillary layer/region -L- | areolar connective tissue that has many blood vessels which nourish the epidermis and are involved in thermoregulation. contained dermal papillae and is thin and superficial to reticular layer |
dermal papillae -L- | Messner's corpuscles (touch) and free nerve endings (pain)detect stimuli. - help create large ridges in fingers and feet for finger printing |
subcapillary plexus | capillary loops |
reticular layer -L- | dense irregular tissue and collagen in extracellular matrix. - functions for strength, elasticity and collagen which binds water to keep skin hydrated. accounts for 80% of dermis |
contributers to skin color | melanin, carotene and hemoglobin |
melanin | polymer of tyrosine amino acids creating a clor from yellow to brown or black |
tyrosinase -L- | enzyme that is the key to production in melanin |
carotene | orange pigment found in plant products . accumulates in stratum coreum and in fatty tissue of hypodermis resulting in orangish tinge |
eumelanin -L- | brown to black pigment synthesized in ellipsoidal melanosomes |
pheomelanin -L- | yellow to red pigment synthesized in spherical melanosomes |
exterorecptor -L- | a receptor that detects stimuli external to the body |
exteroreceptor structure -L- | unencapsulated or encapuslated (connective tissue encircles nerve ending) |
unencapsulated nerve endings -L- | free (naked) dendritic nerve ending and root hair plexus |
free (naked) dendritic nerve ending -L- | detects pain (nocioceptors), heat/cold (thermoceptors), and stretch (proprioceptors). - found in body tissue dermis, cornea, ligaments, tendons |
root hair plexus -L- | detects movement of hair. - found in and around hair follicles |
encapsulated nerve endings -L- | meissner corpuscle - ruffini's corpuscle - pacinian corpuscle - krause's end bulb |
meissner corpuscle -L- | feels light touch. - found in dermal papillae, especially in hairless skin |
ruffini's corpuscle -L- | feels stretching, deep and continous pressure. - found in dermis, joint capsules and subcutaneous tissue |
pacinian corpuscle -L- | feels pressure and vibration. - found in subcutaneous tissue and dermis |
krause's end bulb -L- | feels light touch. - found in mocous membrane (moving down esphagus |