- 4 hours ago
Facts you didn’t know about your body + animal bodies! Check it right now!
Category
🎈
FunTranscript
00:00Now, I've tried this one myself, too.
00:02Pinch your elbow as hard as you can.
00:04You barely feel pain.
00:06How come?
00:07Well, different areas of your skin have different nerve endings.
00:11Our bodies are designed to be more sensitive to pain in places that are at higher risk of getting damaged.
00:17Those important parts have more nerve endings so that we're more alert and able to protect ourselves.
00:23And thick skin, like that on elbows, has fewer pain detectors.
00:26Now, I'm not talking about the tingling, jolting pain you can feel when you hit your elbow against something.
00:33Oh, that feels almost like your entire arm has been electrocuted.
00:37It's not a feeling I would consider funny, but it comes from the funny bone.
00:41Now, the funny bone isn't actually a bone.
00:44It's a nerve that starts in your spine, goes through your neck, through your elbow, and through your fingers.
00:50Its real name is the ulnar nerve.
00:52It's one of the three primary nerves in your arm, and it provides sensation to the fingertips.
00:58Your ulnar nerve is well protected by muscle, fat, and bone.
01:02But there's one spot at your elbow where this nerve is exposed, and that spot is...
01:08Yeah, the funny bone.
01:09A different but real version of Achilles' story, huh?
01:13Okay, so now you know why it hits so different when you bump your funny bone,
01:17and why you feel nothing when you pinch your elbow.
01:20Now, the next phenomenon is related to socially awkward moments.
01:24Okay, maybe not entirely.
01:26It might happen when your crush gives you a compliment.
01:29I'm talking about blushing.
01:31Now, I'm not sure those butterflies in your stomach exist when you're in love.
01:36But I'm sure of this.
01:37When you blush, your stomach lining also turns red.
01:41Yeah, I've looked.
01:42The stomach lining is the tissue that protects your stomach walls from the acid inside.
01:47When you blush, it also turns red,
01:50because blushing happens when the blood rises to the surface of the skin.
01:54This affects the stomach too.
01:56Now, this is a natural process, a physiological response to the change in your emotions.
02:01Now, since we're talking about the stomach,
02:03it might be a good time to mention that the stomach fluid has the ability to melt a steel table.
02:10Yup.
02:10This means the acid would be able to digest your internal organs.
02:14Luckily, the stomach lining prevents this from happening.
02:18Number three is about letting you know that you can glow in the dark.
02:21Now, don't turn off the lights just yet.
02:23You can't see it with the unaided eye.
02:26These visuals of glittering human bodies come from ultra-sensitive cameras.
02:31Japanese scientists were the first to capture the images of human bioluminescence.
02:35Only ultra-sensitive cameras can reveal that our bodies emit tiny amounts of light,
02:41because this light is a thousand times weaker than the human eye can detect.
02:45Apparently, all living creatures produce a small amount of light thanks to the chemical reactions in their cells.
02:51Humans are newly added to this list.
02:54The researchers had been photographing the upper bodies of the volunteers for several days.
02:59The results showed that the amount of emitted light followed a 24-hour cycle.
03:04The glow is at its highest in late afternoon and lowest late at night.
03:09Plus, the brightest light is emitted from the cheeks, forehead, and neck.
03:13Interestingly, this does not correspond with the brightest areas caught by thermal cameras.
03:19Did you know you're a little bit taller in the morning than you are later at night?
03:23Yes, I've been measuring you.
03:25Seriously.
03:26This height difference is related to gravity.
03:29Its force compresses the cartilage in your spine and knees when you stand up or sit down throughout the day.
03:35But when you're lying down, your spine decompresses and relaxes.
03:39That's why, when you wake up in the morning, after resting in bed all night, you're taller.
03:44The increase in height is not even above an inch, so don't bet on who is taller after hearing this
03:50information.
03:51Fun fact, astronauts returning from a mission are a few inches taller than they usually are on Earth.
03:57It's because of the lack of gravity on the International Space Station.
04:00They don't remain that tall forever, though.
04:03When they're on the Earth again, gravity gradually squeezes them back down to their usual height.
04:08Now, let's get back to the organ we've already spoken about, the skin.
04:13Yes, the skin is an organ.
04:15In fact, it's the largest organ in your body.
04:17It contributes to about 15% of your body weight.
04:21What else does this organ do, besides covering your body?
04:24It performs vital functions.
04:26For instance, it protects your body from external physical and biological harm.
04:31Plus, it prevents excessive water loss.
04:34Now, I can't help wondering what other surprises the human body has in store for us.
04:38But right now, let's move on to the animal planet.
04:43Owls don't have eyeballs.
04:45Instead, they have something called eye tubes.
04:47Their rod-shaped eyes do not move in their sockets as our eyeballs do.
04:51That's why owls would have to move their entire bodies to look around.
04:56But moving their torsos would make some noise, and other animals would hear it.
05:00So owls have evolved to have necks that can twist to around 270 degrees, and they move super silently.
05:08But why the concern?
05:10Well, night vision requires large corneas to get as much light as possible.
05:14This is the main reason why most nocturnal animals, such as the slow loris or tarsier, have big eyes.
05:21For owls, it works a little differently.
05:23Since they have small heads, such large eyes wouldn't be able to fit inside.
05:28Now, even though these creatures don't have eyeballs, they have three sets of eyelids.
05:33One set is for blinking, one is for sleeping, and the last one is for keeping their eye tubes clean.
05:38So, do the owls give a hoot about that?
05:41Yes, yes they do.
05:42Moving on from nocturnal animals to the ones you're more familiar with.
05:47Meow.
05:48Cats have an extra organ that allows them to taste scents in the ear.
05:52This organ is called Jacobson's organ, or the vomeral nasal organ.
05:57Jacobson's organ is located inside the cat's nasal cavity and opens into the roof of the mouth.
06:02This organ can detect specific chemicals by using nerves that lead directly to the brain.
06:07That's not a regular sniffing, though.
06:09The odor receptors of Jacobson's organ aren't designed to catch ordinary smells.
06:14They detect chemicals that have no odor at all.
06:17In other words, cats can detect undetectable smells.
06:21It's not just this.
06:23Jacobson's organ increases the sense of smell.
06:26For instance, when kittens need to find their mother's milk, imagine there are two mother cats and four kittens.
06:32Kittens can distinguish their mother from the other grown-up cat with the help of their sense of smell.
06:38Now, when two people meet, they assess each other's body language.
06:42Cats can usually do this by sniffing each other's heads.
06:45This greeting releases pheromones that can tell a lot about one cat to the other,
06:49like what the other feline likes to eat or if they are healthy or not.
06:53They can even evaluate whether the other cat is happy or moody, all thanks to Jacobson's organ.
07:00Now, another fact about cats.
07:02Their nose has distinct ridges that look like a pattern.
07:05Similar to our fingerprints, every cat has a unique nose print.
07:09It can be used as a form of identification.
07:12Okay, cat, we can nail you for breaking the vase.
07:15We have your nose prints all over it.
07:17Now, do you want to cut a deal?
07:18Just tell us what you know about the dog and that chewed-up DVD.
07:23Dog lovers, no, I didn't forget about you.
07:26Here's a myth you've probably heard.
07:28Dogs are colorblind.
07:30But they aren't.
07:31However, it is true that the color range they can detect is limited compared to the spectrum humans can see.
07:38Their color palette consists mostly of yellows, blues, and violets.
07:42Our reds, greens, and oranges are not noticeable to them.
07:45Now, this one is about turtles.
07:47These animals cannot leave their shells and get back whenever they want.
07:52In fact, they are completely attached to their shells.
07:55These shells grow with turtles, similar to the human skin.
07:58A turtle's shell consists of 50 bones.
08:01It also includes a skeleton with the spine and ribcage.
08:05So, they go on vacation with it.
08:07It's kind of like an RV that you can't get rid of.
08:11You know what?
08:12In 10 years from now, you'll be a completely different person.
08:16Well, at least your skeleton will be.
08:19To reach its adult size, your skeleton went through a process called modeling, which means the development of growth and
08:25formation.
08:26Turns out it regenerates completely once every 10 years or so.
08:30This entire process ensures you always have healthy bone cells, which can support you and provide calcium to your body.
08:38And speaking of ways the body regenerates, every second you make 25 million new cells.
08:44I'll do the math for you.
08:45Okay, that means in about 15 seconds, you'll have made more cells than there are people in the United States.
08:52Think about that the next time you feel you haven't been productive enough.
08:57Some animals have eyes that need to adapt to hot climates, like camels, for example.
09:03Their eyes feature a third eyelid, but these sweep across from the corner of each eye.
09:08Because their environment is filled with small particles, they need to clean their eyes more frequently than other species.
09:15Now, see that little pink thing in the corner of your eye?
09:19It's also a third eyelid.
09:21Well, a vestige at least.
09:22In humans, the third eyelid is unnecessary because it no longer serves its original purpose.
09:30Next time you're tuning in to your favorite song, try to pay some attention to your heartbeat.
09:35If you listen closely, you'll notice that sometimes your heartbeat may synchronize with the rhythm of the song.
09:42Now, not all genres of music have this special ability.
09:46But some tunes trigger the release of dopamine, or the happy hormone.
09:51Now, this effect may give you a lower heart rate, breathing rate, and blood pressure.
09:56And speaking of that healthy ticker of yours, just in case you're wondering, it beats on average about 75 times
10:03per minute.
10:04This means each year, a human heart can pump enough blood to fill an Olympic-sized pool, if that were
10:11a thing.
10:12What's even more fascinating is that if you were to connect all your blood vessels end-to-end,
10:17it would be able to circle the Earth two and a half times.
10:20But that's not good for your own health, so don't do that.
10:24Your heart can also continue to beat even if it's removed from the body.
10:29That's because it has its own internal battery, which allows it to beat as long as it receives oxygen.
10:35If you regularly have your nails done at a salon, you've probably noticed you need more appointments for your fingers
10:42than your toes.
10:43That's because fingernails do grow faster.
10:46The definitive scientific answer is still up for debate.
10:49But many specialists think it's because fingernails used to be claws, somewhere back in our ancient history.
10:55These days, they're flatter and have widened a bit.
10:59And it all happened when primates started using tools in their day-to-day lives, like stones and branches.
11:05So there was less use for claws.
11:07Once they got flatter, it meant nails wouldn't have gotten in the way if primates wanted to use the palms
11:13of their hands.
11:15As for why fingernails grow faster than toenails, the short answer may be the fact that we use our hands
11:21more than your feet.
11:23As such, our fingernails are more exposed, and we may have evolved to grow them faster.
11:28The more you use a certain part of your body, the more it becomes exposed to damage.
11:33So for me, I'm in danger of my mouth falling off.
11:37Oh boy.
11:40Getting back to our hands, it's about time we give a nice shout-out to our humble pinkies.
11:45We don't see them as being really that important, since we don't use them for holding objects, eating, or writing.
11:51But recent studies have shown that losing the pinky on our dominant hands would have a devastating effect.
11:58Specialists haven't gathered enough data to supply specific numbers,
12:02but from what they've learned so far, losing our pinky would weaken our grip strength considerably,
12:08even if it's the lesser-used finger.
12:10Adding the ring finger to that and the effect would be worse for our grip strength.
12:16Another recent study done in the UK has shown that only about 40% of people are happy with how
12:23their nose looks.
12:24Regardless of how you feel about it, the human nose is a real-life superhero.
12:29That's because it acts as a heater, filter, and humidifier all at once.
12:34Inside each nostril, there are small, shelf-like bones that feature blood vessels.
12:39They heat the air up before it reaches other parts of our respiratory system.
12:44The mucus that's inside there handles making the air more humid.
12:49As for the filtering part, that's why we have nose hairs.
12:52Small particles get stuck on these small hairs, which helps prevent pollen, spores, viruses, or bacteria from reaching our lungs.
13:01Now, when watching cartoons, we're led to believe that the sound our heart makes
13:06is because it's touching its environment while beating.
13:09Well, it turns out that sound is actually made by the opening and closing of the heart valves.
13:14They're like small doors inside our hearts that open and close to pump blood correctly from one side of the
13:21heart to the other.
13:22For our bodies to work, blood needs to move at the right time and in the right direction, or else.
13:30Now, let's talk teeth.
13:32Throughout your entire life, you'll probably spend up to 40 days total just brushing your teeth.
13:38And in case you're still wondering, teeth are not in fact bones, even though they do have a lot in
13:43common.
13:44One of the primary differences between bones and teeth is that our bones can regenerate.
13:49They are living tissue.
13:51Our teeth are not, and they remain permanently damaged once broken.
13:56Now, here's another shocker.
13:58Ooh, we are the only species on this planet to have a chin.
14:01There's still some debate about this subject in the scientific community,
14:05but one of the reasons why seems to be to make our jaws stronger.
14:10As humans have continued to evolve, their teeth and the muscles in their jaws got smaller and smaller.
14:16So they needed something to help with increased jaw resistance.
14:21Now, most of us have developed some specific traits depending on the area of the globe in which we live.
14:28But there is a group of people, specifically those who live in higher altitudes,
14:33that develop some pretty cool traits.
14:35That's because high-altitude environments come with less oxygen.
14:39Not only do these people survive in these locations, but they've adapted so well that they actually thrive.
14:46In the Andes Mountains of South America, people have evolved red blood cells that can carry much more oxygen.
14:52It makes their overall circulatory system much more efficient.
14:56People living in Tibet have to endure similar conditions, but surprisingly, they have adapted differently.
15:02In Tibet, they can take more breaths so that they can properly oxygenate their bodies.
15:09You've probably heard the myth about dreams only lasting a couple of seconds in reality.
15:14Turns out that, yes, some of them do, but not all dreams are the same.
15:19There are a lot of things we don't understand yet about how we dream.
15:23What we do know is that they mainly happen during the rapid eye movement, or REM, stage of sleep.
15:30During this time, your brain is more active, about as active as it is when you're awake.
15:34And it's named REM because, during the sleep stage, your eyes tend to move a lot.
15:40Dreams can happen during the other stages of sleep, too, but you're less likely to remember them.
15:46As for the length of each dream, they can go from a few seconds to even 20 to 30 minutes.
15:53Also, you're more likely to remember a dream if you've woken during the REM stage.
15:57Most people have three to five dreams per night, but some people can have up to seven.
16:03I know, seems unlikely, but remember, you immediately forget most of what you dream.
16:09Just like we have unique fingerprints, we also develop unique tongue prints.
16:14Research has shown that those approximately 10,000 taste buds on our tongues are laid out in a one-of
16:21-a-kind pattern.
16:22Truth is, about 80% of what you believe is taste is actually smell.
16:27That combination of taste and smell that we perceive is what we come to know as flavor.
16:32That's probably because our sense of smell is around 10,000 times more sensitive than our sense of taste.
16:39Our mouths have also another cool superpower called mouthfeel.
16:44With the help of a somatosensory system, it allows us to sense the texture of our food.
16:50The system is activated by physical touches, such as pressure, touch, or vibrations.
16:55It's even sensitive to pain and temperature.
16:59We also use our tongues to identify the size, form, and texture of food, which is crucial for proper chewing
17:05and digestion.
17:07Hey!
17:07Tongues are also good for wagging, sticking out at certain people, and trumpet playing.
17:14You have as much hair as a monkey.
17:17Now, I don't mean to be insulting, but your fingerprints are not unique.
17:21You can hear better after you cover your ears.
17:24Now, can these statements be true, or are they nothing but myths?
17:28When a person is lying, their own nose can give them away.
17:32Can it be true?
17:33Can it be true?
17:40Yep.
17:41Researchers from the University of Granada have discovered that when a person tells a lie,
17:46the temperature around their nose and in the inner corners of their eyes rises.
17:51This phenomenon got named the Pinocchio effect.
17:55Hey, how about this one?
17:57People can have as many hairs on their body as chimpanzees.
18:01Can you believe this?
18:08Surprisingly, this one's true, too.
18:11The hair count of a person and a chimp, or any other ape of our size, is approximately the same.
18:17The only difference is that human body hair is quite fine and often colorless.
18:22This makes it hard to see the sheer number of hairs.
18:26Your lungs are identical.
18:28It sounds reasonable, but is it true?
18:37Well, it's nothing but a myth.
18:39Your left lung consists of two lobes, while your right lung is divided into three parts.
18:44Plus, the lung on the left is a bit smaller.
18:47It has to, to make room for your heart.
18:50By the way, your lungs also contain around 1,500 miles of airways.
18:55It's more than half the distance between New York and Los Angeles.
18:58There are also more than 300 million alveoli, tiny balloon-shaped air sacs, in your lungs.
19:06I bet you've heard this one before.
19:08Carrots can make your eyesight better.
19:09True or myth?
19:17Unfortunately, this idea isn't true.
19:20Neither can carrots get you better nighttime vision.
19:23Carrots are indeed packed with vitamin A.
19:25It benefits your body and protects your eyes.
19:28But even these veggies can't save you from wearing glasses if you need them.
19:33Some people sneeze when looking at the sun.
19:35Now, do they?
19:44Yes, that's true.
19:46About 25% of people have an interesting reaction to sunlight.
19:49They sneeze.
19:50This phenomenon even has its own name.
19:53The photic sneeze reflects.
19:57Shaving body hair makes it grow darker and thicker.
20:00Is it the truth?
20:07Don't worry, that's just a myth.
20:09It might look as if your body hair has changed in thickness, rate of growth, or even color after getting
20:15shaved.
20:16But it's just an illusion.
20:18Shaving makes the tips of hair follicles blunt.
20:21That's why they look rougher and darker than usual.
20:23But once your hair grows in again, it'll start to look the same as it did before you shaved it.
20:30You have unique fingerprints.
20:32Ah, this one must be true, right?
20:39The problem with this statement is that scientists can't prove that each set of fingerprints is absolutely unique.
20:45It does seem to people, but it's impossible to check.
20:49And while this is improbable, people with identical fingerprints can actually turn out to be real.
20:55People have more than five senses.
20:58Is it an appealing myth or reality?
21:06There are five most obvious senses.
21:09Vision, smell, touch, hearing, and taste.
21:12But how about thermoception, the sense of heat?
21:16Noceoception, the perception of pain.
21:18Or the perception of your body awareness.
21:21Proprioception, close your eyes and touch your nose.
21:24Got it?
21:25That's proprioception and action.
21:27This list can be much longer.
21:29Some experts state people have from 21 to 53 senses.
21:34Your fingers actually get pruny after you spend too much time in the water for your safety.
21:39Is it true?
21:40What's your bet?
21:47Scientists believe so.
21:48But first things first, pruny fingers are caused by narrowing blood vessels.
21:53When you stay in the water for a long time, your nervous system makes your blood vessels shrink.
21:58Your body sends the blood away from that area.
22:01And this loss of blood makes your vessels thinner.
22:04The skin starts folding over them, forming those funny wrinkles.
22:08Scientists aren't 100% sure.
22:10But they think this process occurs to help you have a better grip when your hands and feet are wet.
22:16People only use 10% of their brains.
22:18Oh, how I wish it was just a myth.
22:26And it is!
22:28Apparently, you use almost 100% of your brain every day.
22:32This organ is active all the time, even when you're asleep.
22:35When you're snoozing, your frontal cortex, which is responsible for higher-level thinking,
22:41and the areas that help you sense your surrounding, are still doing their job.
22:46For some people, the world is much brighter than for others.
22:50Hmm, how come?
22:57That's actually true!
22:58There are three kinds of cone cells in the average person's eyes.
23:02These cones help to recognize the colors in the blue, red, and green spectrums.
23:07Thanks to them, most people can distinguish around 1 million different shades.
23:12But those with technochromacy have 4 cones in their eyes.
23:16This feature allows them to see up to 100 million different hues.
23:20This vision anomaly is extremely rare, and women have it more often than men.
23:26But do you know the funniest thing about this?
23:28Most people with technochromacy don't even realize they see the world brighter than others.
23:34Sometimes, you can hear better after closing your ears.
23:37Well, it seems counterproductive.
23:39But can it be true?
23:46Indeed, if you're in a loud place,
23:49For example, in a club or at a concert,
23:51you should close your ears to hear your friends better.
23:54Push the tragus, which is the pointy skin-covered cartilage in front of your ear canal,
23:59into your ear.
24:00Then turn this ear toward your friend.
24:03Voila!
24:05You can prevent yourself from sneezing.
24:07Oh, that would be very convenient.
24:09But maybe it's just a myth.
24:17It's true.
24:18If you don't want to sneeze,
24:19press the skin on the bridge of your nose with your fingers.
24:22When you do it,
24:23your brain receives an alarm signal.
24:26It immediately puts the brakes on all other processes,
24:29including the sneezing reflex.
24:32Okay, you're going to finish these 5 episodes of your favorite series now,
24:36and catch up on sleep later.
24:38But can you?
24:45Unfortunately, no.
24:47You can try to catch up on sleep at the weekend or take lots of afternoon naps during the week.
24:52But it won't help.
24:54Your body doesn't work this way.
24:56If you didn't have enough sleep the night before or went to bed really late,
25:01sleeping until noon won't save the day.
25:04Even worse, too much sleep will make you feel groggy.
25:08Some people have more ribs than others.
25:10Is it a myth?
25:18Nah, it's true.
25:19Most people have 12 pairs of ribs,
25:21which makes 24 in total.
25:23But 1 in 200 people has an additional 25th rib.
25:27It's called cervical and forms at the base of the neck, above the collarbone.
25:32It can grow on the left, right, or even both sides of the body.
25:36Those people who have extra ribs most likely know nothing about this modification.
25:41That's because an extra rib rarely forms completely
25:44and can look like a thin strand of tissue.
25:46In this case, you won't see it even on an x-ray.
25:50You should wait for at least a half an hour after eating before you go swimming.
25:54Well, it sounds reasonable, but is it true?
26:02Ah, that's just a myth.
26:04The general idea behind this claim is that eating a large meal
26:08makes your blood flow towards your stomach to help with the digestion process.
26:11At the same time, your muscles don't get enough blood, which leads to cramps.
26:17But in reality, swimming right after having eaten something isn't dangerous at all.
26:22Your blood doesn't get diverted enough for it to cause any serious problems.
26:27Some people's snores can get louder than a working kitchen appliance.
26:31What do you think about this?
26:38Well, on average, when a person snores, the sound doesn't get louder than 60 decibels,
26:44which is as loud as a regular conversation.
26:47But sometimes, the noise level can reach 80 decibels,
26:50and that's as loud as a working food blender.
26:54Not all people have round pupils.
26:57Can it be true?
27:04Yup.
27:05Two people out of every 10,000 have an unusually shaped pupil.
27:10Most commonly, it resembles a keyhole.
27:12This eye disorder is called coloboma.
27:15Interestingly, some people with this condition
27:17don't have any problems with their vision.