almost all of our body is covered with hairs even if we don't notice them they grow even in the belly button their purpose is to catch lint check it out see a single human hair can support 3.5 ounces of weight that's how much two candy bars weigh.
Our hair color is easily explained by jeans there's not more than two percent of people with natural red hair they're followed by blondes and by all the varieties of brown shades the vast majority goes to black hair including very dark brown yeah your hair can stop growing at a.
Certain length a hair usually grows from two to seven so usually it doesn't exceed 42 inches well tell that to this gal from china who broke all the hair records with the longest hair ever in 2004 her hair was 18 feet 5 and a half inches long with age your hair loses its natural color it happens because keratin.
Receives less pigment as people grow older the pigment cells in their hair follicles gradually vanish and hair becomes gray some time passes and no pigment is produced at all that's when hair turns white the only part of the human body that doesn't get any nutrients from blood is.
The cornea of the eye instead it's fed by tears and fluid in front of your eyes a human eye has some resemblances to a car engine they both need various liquids to perform properly an engine needs gasoline and an eye needs tears in order to work well the tears should be thoroughly distributed.
All over the eye that's why we blink up to 20 000 times a day so a lid is a bit of a windshield washer we've got two really fast muscles they control the eyelid closing they're the fastest muscles in our body eyes are fragile and need protection that's why when the reflex is triggered these muscles shut the eyes within about.
100 milliseconds no more than 0.1 seconds we recognize only purple blue green yellow and yellow red colors everything else is a combination of these three it's impossible to calculate how many of these combinations the human eye sees because every single person has slight vision differences.
But it's about one millionth combinations on average you see the inability to distinguish colors also known as color blindness affects around 8 percent of males and 0.5 percent of females but colors themselves aren't as stable and objective as they might seem multiple tests have shown that people.
Experience colors differently depending on many factors such as geographical location language and gender to name a few it means that you can enjoy the same sunset with your friend and see completely different colors without even knowing it just like fingerprints your eye color is.
Unique it can even affect the way you perceive light and make your vision one of a kind to understand how this is possible you gotta figure out how the eye color is formed this is the iris the colored part of the eyeball the iris contains pigmentation and its.
Content determines what eye color you have every human has a slightly different amount of pigmentation that's why you won't find two people with identical eye colors three specific genes in your body are responsible for melanin levels and determine pigmentation.
Blue and green eye people have less melanin in their iris and those who have more melanin have darker eye colors like brown and hazel some rare people have beautiful deep black eyes but this is only an optical illusion caused by the abundance of melanin pure black iris doesn't exist in nature.
Although these eyes look very dark they're actually dark brown studies have proved that eye pigmentation impacts your vision no matter how dark or light your eye color is people with lighter eye colors are more sensitive to light which may cause them to feel uncomfortable on sunny days.
If you have a light eye color and have to squint when you go outside don't forget to put on sunglasses your irises contain less pigment that serves as protection from the sun's rays but since melanin acts like natural sunglasses you have better night vision compared to dark-eyed people on the contrary if you have a darker eye color your eyes can.
Cope with bright light better during the daytime dark eyed people should feel more confident while driving at night because they don't get blinded by car headlights that much your peripheral vision is almost completely black and white it's because you have more color.
Detecting cones in the center of your retina than at the sides women can distinguish more colors than men because they have two x chromosomes and men only have one even if something is wrong with one of the chromosomes a woman can still see colors correctly that's why women are rarely colorblind.
There must be at least some photos where you have red eyes when the camera flash goes off your eyes aren't prepared for such an influx of light your pupils remain dilated which is why the light gets reflected off the red blood cells of the choroid this is a layer of tissue at the back of your eye that nourishes your retina.
The weird-looking flies you see right in front of your eyes every now and then are eye floaters you see them because of tiny structural imperfections in one particular part of the eye that gets in the way of light they get worse with age you spend ten percent of the time when you're awake with your eyes closed it's.
All those times you're blinking humans are capable of using echolocation like bats and dolphins with some training you can find your way in complete darkness analyzing the surroundings by sounds bouncing off objects dope need to practice that about six percent of people can vibrate and rapidly shake their eyeballs back.
And forth it doesn't mean something's not right with their eyes it's just a unique trick they can perform the main purpose of eyelashes is to shield your eyes and protect them from sand moisture dust and debris in the air your eyelashes sense when something comes up too close to your eyes like an.
Insect flying towards you and trigger your blink reflex blinking also helps when you need to flush out some tiny particles or debris stuck in your puncta those are small openings you have in your eyelids that's where the tears get pumped out your eyebrows stop sweat from running directly into your eyes your skin there.
And the shape of your bones also work together to direct the sweat towards the sides of your face onions produce a special chemical irritant it stimulates special glands in your eyes causing them to release tears the nose is probably one of the most underappreciated parts of the body we wouldn't even be able to enjoy eating.
Without it about eighty percent of the taste of any food is thanks to the nose and its ability to recognize odors if you hold your nose while eating you will taste almost nothing with no sense of smell you're likely to recognize food mostly by texture so an onion might seem no different than a big refreshing apple.
Scientists used to believe we could distinguish about ten thousand smells but they were wrong recent research showed that people are actually able to distinguish between more than a trillion smells we also remember them better than anything else and smells can even evoke some distant memories.
Your nose doesn't just help you breathe and catch odors it filters the air for sensitive throats and lungs if we inhale dry air the nose moistens it cools it and heats it if necessary also the nose cleans the air of dirt your nostrils don't work with the same efficiency all the time when you breathe one nostril does most of the work and.
They switch every couple of hours eighteen percent of people can move both ears at the same time while 22 percent can move one ear at a time people who can do it use weak vestigial muscles we got from our ancestor humans who had this trait in common with cats some people can produce a roaring noise.
In their heads all they have to do is tense their ears or jaws there's a small muscle in the ear it dampens loud sounds like when you're chewing but some people can flex that muscle and that creates an audible rumble your teeth are the only part of your.
Body that cannot heal itself