okay in this video we're going to talk about sweat glands uh sweat glands are also called cerous glands and all skin surfaces except for the nipples and external genitalia uh contain sweat glands in fact you got about three million of these per person and there are two major types of puder or SW LS we got the erine or marrine Sands and they're Nam this because they use a marrine form of secretion and then apocrine SWAT glands are also another variety now these contain myoepithelial cells which contract on nervous system simulation to force sweat into the ducts and onto the skin surface and the marrine uh sweat glands also called echine these are the most numerous you find these on your palms soles your feet and forehead most abundantly uh these ducts connect to pores on the surface of your skin and these are mostly involved with Thermo regulation theral regulation meaning that we can actually cool our body temperature down uh by sweating and relying on the EVAP ative cooling properties of water and uh it's actually regulated by your sympathetic nervous system which is the fight ORF flight uh response so if you're excited then you're going to sweat and this is going to help to cool your body down now the secretion of sweat is mostly water followed by salts some vitamin C uh antibodies which is actually an immune element uh dermon which is a microb killing peptide as well as other metabolic wastes so some wastes are also incorporated into sweat and you find that in conditions like renal failure where if your kidneys can't get rid of wastes you know your sweat glands actually end up secreting a lot of these wastes and you end up with something called uh ureic Frost which is essentially kind of a salty uh coating of the skin due to an accumulation of these wastes now in sweat rather than urine so uh what do these Ean sweat glands look like well essentially they there's these tubular glands that are highly coiled you find them embedded within the dermis and then those drain into a duct which then uh winds up and then empties on the surface of your skin through a sweat pour so that sweat is essentially drained onto the surface of skin via this duct now remember the way that sweat actually gets up onto the surface of skin are those myoepithelial cells because the myoepithelial cells would surround the ducts and then essentially help to squeeze that fluid up and out of the duct towards the skin surface now this differs from the apocrine sweat glands uh apocrine sweat glands are confined to the axillary and anogenital areas when you think of anogenital think of like perenium which is essentially the space between the external genitalia and the anus now apocrine sweat glands secrete a more viscous milky or yellowish type of sweat that contains fatty substances and proteins um now this is the one that's these aren't as active until puberty and uh their function is really unknown but they probably act as a sexual scent gland land because these viscous milky substances have a lot of protein could be pheromones that are involved with you know sexual communication through pheromonal communication uh it turns out that the bacteria on your skin also like to break down and digest these substances in sweat and this is what leads to body odor so body odor and the um you know axillary which armpit or anogenital areas groin uh this is associated with bacteria eating apocrine secretions in the metabolites of those bacteria are what cause body odor now these apocrine sweat glands are much larger than erine sweat glands and they're ducts empty on the hair follicles rather than on the surface of skin so you only find apocrine SWAT glands associated with hair specifically the hair of your axillary and anogenital areas these aren't really involved with Thermo regulation they're most likely involved with uh sexual scent uh fer monal communication now uh there are other modified sweat glands as well like ceruminous glands or mamory glands ceruminous glands are the ones that line your external ear canal and they they they secrete cumin which is basically ear waxs and uh mamory glands are also a modified type of apocrine secretion and this is what creates uh breast milk so what's fascinating is that these are just similar varieties of apocrine glands uh in different areas of the body now uh oil glands are the ones that are associated with a hair follicle they're widely distributed except for the thick skin of your palms and now these sebaceous or oil glands are associated with hair follicles and they're relatively inactive during puberty uh therefore stimulated by hormones especially androgens and the type of oil that these create is actually called sebum sebum is this oily holocrine type of secretion remember the entire cell bursts to become the secretion here and it also contains bacterio cyal or bacteria killing properties and it helps to soften hair and skin so in that sense that sebaceous glands help to condition your skin so you find sebaceous glands associated with hair follicles as we can see here um in fact the duct of these sebaceous glands drains right onto the hair shaft or the hair root rather and that way the growing hair brings oil up to the surface of skin with it and it make sure that the hair is conditioned and your skin is well conditioned