What if You Had No Skin

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if you had to guess what the biggest
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organ in your body is what would you say
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your lungs are pretty huge right or
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maybe your liver which weighs about as
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much as for FIFA approved soccer balls
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you might not think it but your biggest
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organ is actually mostly on the outside
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that's right it's your skin if you
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stretched out all the skin on the
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average 150 pound adult man it would
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cover over two square yards and weigh
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around nine pounds that's pretty darn
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large the skin is responsible for a
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whole range of processes that keep us
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going day-to-day but what would you do
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without it stick around to find out
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[Music]
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first up the basics what actually is
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your skin well the skin is made up of
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three main layers which all work
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together as part of the integumentary
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system the top layer or epidermis is the
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part we can actually see and is made up
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of mostly dead skin cells and acts as a
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protective waterproof wrap for the body
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skin thickness varies throughout the
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body from half a millimeter and its
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thinnest which you'll find on your
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eyelids to four millimeters on the soles
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of your feet the second layer the dermis
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helps to maintain the epidermis by
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diffusing nutrients to it and replacing
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skin cells that are shed off of upper
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layers this is also where you'll find
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hair follicles sweat glands blood
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vessels and a whole bunch of nerve
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endings and touch receptors that help us
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navigate the outside world
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the vinyl bottom layer is known as the
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sub judice which is composed of
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subcutaneous fat which insulates and
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helps cushion us when we bump into
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things and connective tissue that binds
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the skin to muscles beneath you should
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think of your skin as your body's main
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line of defense
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it might sound kind of obvious but
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without your skin holding everything
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nicely in place you'd be nothing but a
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soggy mass of tissue bodily fluids and
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internal organs basically you'd end up
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as a gelatinous blob on the floor which
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isn't as a good look for anyone skin
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also has some pretty cool regenerative
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properties which can heal you whenever
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you get a cut or scratch as we know the
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epidermis is constantly shifting off
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replacing skin cells known as
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keratinocytes and the entire layer
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actually gets renewed completely every
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four weeks as new cells head toward
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the surface they're filled with a
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hardened protein called keratin when
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they reach the top is overlapping skin
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cells form a protective barrier that
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stops any nasty harmful bacteria from
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getting in although we may not notice it
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your skin is also constantly making sure
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that you stay just the right temperature
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which fYI is about 98.6 degrees
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Fahrenheit if your temperature falls or
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Rises dramatically part of your brain
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called the hypothalamus sends a message
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to the skin to help regulate it when you
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get too hot blood vessels move warm
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blood to the skin surface so that the
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heat can be released sweat glands also
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produce sweat which helps cool you as it
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evaporates likewise the skin can cause
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blood vessels to contract moving warm
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blood away from the surface and toward
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our vital organs to keep us warm when
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tiny muscles beneath the skin known as
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erector pili cause hairs on our skin to
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stand up and when these muscles tighten
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and release quickly this causes a
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sensation we call shivering finally your
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skin is responsible for one of the five
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key senses touch without it your brain
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wouldn't receive all the information it
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needs to navigate the natural
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environment which is based on accurate
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readings of temperature humidity and air
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pressure on a daily basis your skin is
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processing thousands of different
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physical sensations which it does with
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the help of pressure sensitive Merkel
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cells in a single fingertip there are
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750 of these specialized cells per each
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square centimeter of skin which are
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coupled with over 2,500 receptors to
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give you your sense of touch that's some
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serious teamwork now that all that
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sciency stuff is out of the way let's go
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back to the big question what would
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happen if you didn't have any skin for
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you to lose all of your skin in one
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sitting you probably have to be skinned
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alive which while highly unlikely is
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still entirely possible in fact flaying
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as it was once known was a pretty
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popular form of torture and Aztec
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civilization as well as ancient Greece
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China and Africa sometimes the victim
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would be even partly boiled first to
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soften their skin for removal and in
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every case it resulted in an
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excruciatingly ly painful certain death
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a low flame has been banned for
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thousands of years now a similar
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situation could occur as a result of
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some freak accident and one famous case
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a Japanese man ironically named Hisashi
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ouchy lost the
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majority of his skin during an accident
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and a radiation plan he was working at
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ouchy was blasted with 17 sieverts
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radiation which is the highest dose ever
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recorded and is more than double what is
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considered a mortal dose besides severe
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burns all over his body
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ouch his entire immune system and DNA
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were eradicated and his body was left
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near skinless and skeletal miraculously
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he was kept alive for 83 days by various
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procedures including multiple skin
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grafts but he continued to lose fluids
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through the pores of his burns and
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eventually died of multiple organ
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failure and some rare cases it's also
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possible to be born without skin to
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begin with the condition known as
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epidermolysis bullosa affects less than
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1% of all newborns and results in skin
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that is so thin and fragile that it
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blisters and falls off easily this means
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anyone born with the condition must take
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extra precautions to protect their body
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for microscopic attackers and accidental
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injury let's imagine for a moment that
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you were to lose all your skin through
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flaying or some other violent means what
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would happen the most likely cause for
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your immediate demise would be sheer
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shock which anyone would be lucky to
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survive after realizing their entire
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skin was suddenly in a heap on the floor
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unless the whole thing was grafted back
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on immediately something that has never
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been attempted in medical history your
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blood pressure would also drop to zero
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and you'd likely die from total blood
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loss as your blood begins to evaporate
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at an unprecedented rate you would then
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suffer from extreme dehydration if one
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or a combination of these things wasn't
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enough to finish you off it's safe to
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assume that hypothermia wouldn't be far
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behind as we know your skin is a key
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player in regulating the body's
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temperature so without it your vital
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organs would be exposed to the elements
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and would be subject to overeating or
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freezing considering your skin as your
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body's barrier to harmful pathogens
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poisons and irritants in the environment
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you'd be pretty defenseless without it
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even if you hadn't miraculously survived
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the problems I have already mentioned
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you'd have to be some sort of superhuman
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to fight off the multiple infections and
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contaminations that would arise without
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your skin to protect you a condition
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called acute skin failure which occurs
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when the skin fails to carry out one of
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its three main functions often results
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in hypothermia increased fluid and
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routine loss widening of the blood cells
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are vasodilation and infection with that
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in mind it's safe to say that you
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wouldn't really stand a chance if you
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were suddenly stripped of your entire
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skin so perhaps you should start taking
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better care of it there are plenty of
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other parts of your body you couldn't
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live without and your brain definitely
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seems to be one of them or is it the
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brain needs no introductions it serves
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as your central nervous system and
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contains approximately fifteen to thirty
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three billion neurons that control most
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processes in the body that facilitate
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life seems pretty vital to me except the
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truth is you can actually live without
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almost all of your brain and your noggin
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you see although the brain is the most
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complex organ in the body it's also the
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smartest duh but what I mean by that is
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instead of assigning different functions
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to specific areas of the brain each
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section is well equipped to pick up the
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slack and support itself if another part
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is damaged or breaks down unexpectedly
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during this phenomenon known as
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neuroplasticity undamaged axons grow new
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nerve endings to reconnect neurons whose
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links were injured or severed in some
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cases people can also be born with
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congenital abnormalities or early brain
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damage which results in little or no
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function in one hemisphere of the brain
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because this presents a risk of
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debilitating seizures like epilepsy
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surgeons might choose to remove up to
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half of the brain in a surgery known as
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a functional hemispherectomy although
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this can have side effects like loss of
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movement on the opposite side of the
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body for adults it actually has a pretty
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high recovery rate in children and most
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young patients can expect to live a
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normal life afterwards there have been
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plenty of extraordinary cases of people
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surviving with even less than half a
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brain in their skull and 2014 a 24 year
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old woman in China shocked doctors when
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she was found to be missing her entire
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cerebellum without even realizing the
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cerebellum our little brain which is
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located at the bottom of the skull
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contains about 50% of the brains neurons
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and is responsible for coordinating key
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voluntary functions like speech balance
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and posture the woman in question had a
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gaping hole instead which was full of
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nothing but cerebrospinal fluid she
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joins an elite club of just nine people
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who have been known to live happily
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without their entire cerebellum although
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she did admit that she took longer than
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most kids to pick up basic skills like
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speech and an even more surprising case
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of
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34 year old French man who complained of
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weakness and his left leg was sent for a
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brain scan at the University of Marcel
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where neurologists were stunned by what
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they saw there was not much of a brain
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to be seen at all and most of the man's
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skull was taken up by fluid with a small
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smattering of brain tissue lining the
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inside although you would expect such a
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case to be mentally incapacitating the
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man was not disabled in any way and fact
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he held down a job as a civil servant
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and subsequent IQ tests showed his IQ to
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be only slightly below average it may
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seem like these two people were just
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incredibly lucky but both of these
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examples prove just how adaptable the
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brain can be a rare genetic condition
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called Hydra encephalo can also cause
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babies to be born without either of the
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cerebral hemispheres which make up the
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main shape of the brain in 2006 Nebraska
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woman Larina Simpson gave birth to a
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baby girl named Alex who had almost no
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brain doctors predicted that Alex
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wouldn't live past six months but she
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defied medical expectations by
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celebrating her 10th birthday a decade
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later in 2016
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although she requires special care
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around the clock including an overnight
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supply of oxygen Alex is capable of
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basic functions thanks to a little
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sliver of a cerebellum in the back right
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corner of her skull in reality as long
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as you possess the brainstem which sits
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at the bottom of the brain and connects
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to the spinal cord you can continue to
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live this stem is vital in controlling
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crucial functions like breathing
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swallowing digestion eye movement and
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heartbeat which means that without it
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the body cannot sustain life although
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you can survive with reduced life
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expectancy and limited capabilities the
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intricate things that make up the
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concept of use such as memories speech
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identity and personality traits can
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exist fully without vital parts of your
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brain like the cerebellum or cerebral
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cortex so it seems like our skin and our
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brain are pretty vital to living a
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comfortable life but what about bones
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I'll keep this one short and sweet there
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are 206 bones in the average human body
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and about 300 in a newborn which make up
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the essential framework the rest of the
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body hangs on since all of your muscles
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are attached to the bones of your
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skeleton it would be pretty impossible
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to go about daily life without them
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think about it this way the human body
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without bones is just a semi empty sack
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of blood nerves muscles in Oregon
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plenty of animals like octopus jellyfish
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and tarantulas have no interior skeleton
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and get on just fine
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but the same can't be said for us that's
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because every muscle movement including
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the simple act of breathing is totally
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dependent on the support and movement of
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the bones they're connected to without
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your spine to support you you wouldn't
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even be able to stand up without this
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rigid structure to hold you together
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you'd have nothing to protect the very
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things that keep you living like your
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heart or brain and you basically have
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organs popping out all over the place
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which isn't a pleasant thought so there
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you have it your skin brain and bones
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really are vital to your survival so try
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not to lose them anytime soon how long
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do you think you could get by without
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one of these things to keep you ticking
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let me know in the comments below and
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thanks for watching