You would think that they both grow at the same rate. However, that’s not the case. On average a fingernail can be replaced in 6 months, but a toenail will take over a year.

It happens at a rate of about 1 in 500 people. It’s called a cervical rib and can happen on both the left and right side of the rib cage. Even though it is an abnormality, it doesn’t usually cause any problems.

Babies develop very rapidly. After three months of gestation, they already have fingerprints forming. They will then have the same fingerprints for the rest of their lives.

When you kiss someone passionately, your brain releases the same chemicals as it does when skydiving or firing a gun. It’s a powerful cocktail of dopamine, oxytocin, and serotonin.

There are about 100 million new red blood cells being formed in the body every minute. Other tissues have different rates of replacement, but it’s all taking place at the same time as well. It’s a state of constant regeneration.

Both are covered in a pretty incredible amount of bacteria. In some cases, the toilets are actually cleaner than the ATMs. The bacteria may or may not be harmful to the health of humans.

It’s unfathomable how much blood that is. The heart is constantly working, 24 hours a day, 7 days a week. Each heartbeat pumps out about 1/3 cup of blood.

They are apatite, aragonite, calcite, and cristobalite. These mineral crystals are what make up the bones, teeth, and all of the other structural pieces of the body. It is a system that is both simple and complex.

It eliminates the wrinkles, but in turn, makes the facial muscles tighter. The facial expressions you make are directly tied to your emotional state. If you can’t make the full expression, the emotions you feel won’t be as powerful.

It’s a mineral that is crucial to insulin production. The body contains quite a lot of it. If you could extract it all, it would be enough to treat one average dog for fleas.

That is a lot of tar buildup! It can’t be very healthy for the lungs and throat to smoke that much. One cigarette isn’t going to kill you, but years of regular smoking definitely can cause some issues.

They are a remnant of our ancient ancestral past. About 370 million years ago, our ancestors spent a lot of time in the ocean and had both gills and lungs. The hiccup prevented water ingress.

The neurons in the brain are constantly receiving and sending electrical signals. The sheer amount of them is inconceivable. While the impulses aren’t going to be as powerful as all of the phones in the world, there will be more of them.

We’re talking all of the skin on your body. It is in a constant cycle of shedding and being replaced with new skin. This works out to the skin being completely replaced about once a month.

It is the worst day of the week for heart attacks. The risk on Mondays increases by 15% for women and 20% for men. It’s caused both by alcohol consumed over the weekend and the stress of going back to work.

That is 170 miles per hour! In other words, super fast. It only takes a split second for the impulses to be sent from the brain to the nerves.

Yes, some other animals can draw. However, none can connect two points in a straight line. They also can’t construct a perfect circle. These skills are reserved for humans.

Try it for yourself. Rub some garlic on your feet and within 30 minutes, you will start to taste it in your mouth. A compound in garlic called allicin is able to be absorbed through the cell membranes and journey through the bloodstream.

They are able to do this incredible feat for up to seven months. It has to do with a mechanism involved in breastfeeding. Once the babies get older, they can’t do it anymore.

You probably wouldn’t want to. There are much healthier forms of exercise that you can do to burn calories. However, it is possible.

Most humans contain enough blood to feed 1.2 million to 1.8 million of the hungry insects. The body is a literal feast for them. Although, in reality, it would be hard to get bit enough times to lose any substantial amount of blood at any one time.

If it was compared to a computer hard drive, the brain could hold 4 terabytes. Of course, it is difficult to really quantify human memory. There are so many aspects of it that don’t directly translate into computer form.

It’s because kissing someone for an extended period of time causes the acidity in the mouth to normalize. It’s a lot more fun than chewing gum too. You and your partner can kiss away that bad breath.

Having to go forces people to focus on self-control and making fewer extra movements. This, in turn, makes it harder for others to tell if you are lying or not. Therefore, if you plan on lying anytime soon, it’s best to drink a lot of liquid first.

Every other part of your body has a blood supply, but not the cornea. It receives all of the oxygen it needs directly from the air. It absorbs it.

It’s likely you’ll never catch the same cold twice. It’s is possible to have more than one type of cold at once though. There are so many of them and they are always changing.

As many as 70% of people kiss this way. This stat was determined by observing thousands of people kissing. It’s likely that kissing position is associated with right or left-handedness.

The average resting heart rate of women is about three beats per minute faster than that of men. Women between 40 and 49 years of age have the highest average RHR of all. Everyone is different though and there a lot of different factors that determine heart rate.

The phobia is called Parthenophobia. The people who suffer from it normally feel strong social anxiety when around young girls. Sometimes, it results in a full-blown panic attack.

Studies claim that people with higher IQs experience dreams that last longer and are more vivid. However, most people don’t remember their dreams anyway, so it doesn’t really matter that much.

His name was Charles Osborne. He hiccuped non stop from 1922 to 1990. The feat landed him a spot in the Guinness Book of World Records.

The good news is that 95% of them are harmless. The bacteria are largely good for us. However, it does mean that you probably shouldn’t be kissing everyone you meet.

If the same information is read off of a computer screen, it won’t be absorbed into memory as readily. That’s what some studies show. It’s a major win for the fans of the traditional paper book format.

Five minutes after a dream ends, at least 50% of the content of the dream is forgotten. By the fifteen minute mark, that number rises to 90%. After that, all we have are vague notions of what happened.

That is a significant jump from your resting heart rate. It just proves how exciting kissing can be. It really gets the body going.

For a lot of people, a full meal causes a mild ringing in the ears. It might not be very noticeable, but it does have an effect on hearing. It also depends on what you consume. Sweet and salty foods often have a greater effect.

If you lined up all of your blood vessels back to back, they would stretch on for a vast distance. 100,000 km or 62,137 miles is about 2.5 times the circumference of the earth.

They are one of the most sensitive parts of your body. Any contact with human lips instantly creates a noticeable sensation, no matter how light the touch is.

A lot of people think it has no use. However, some scientists now say it serves as a safe home for good bacteria in the body. These useful microbes help to replenish bacteria in the body’s intestines and gut occasionally.

If you find yourself breathing heavier and faster in the spring than in the fall, this is why. Respiration rate changes are seasonal. On average, people’s respiration rate is 1/3 higher at that time of year.

There is a small percentage that ends up in the blood, muscle, and various other tissues. However, the bones are what benefits the most from calcium. It helps to strengthen them.

Just like all the plants start growing more after the winter passes, so do children. It is believed that the increased spring growth rate is due to sun exposure. Some kids can have growth spurts that result in several inches of growth in just a few weeks’ time.

At the end of life, that is the number of pieces of information stored in the brain. It’s an unfathomably large number. It lends some credence to the idea that wisdom comes with age.

If you piled it all up, it would weigh 2 kg or 4.4 pounds. It would include a mix of all kinds of bacteria, both good and bad. Just thinking about all those living creatures makes us a little uneasy.

It’s because it is already digested once by the bees first. Humans get the second go at the sticky sweet liquid. In addition, it is made up of simple carbs that the body can breakdown very easily.

If you want to stay warm, the head is the most important place to cover up. That is where most of the body heat escapes from. Put on a heavy wool hat and you will stay much warmer in the cold weather.

It occurs most often while sleeping. The spiders crawl in and accidentally get consumed. It’s likely that you will never realize it happened.

Surprisingly, they aren’t the same size. It’s because the left lung is positioned over the heart. It has to be slightly smaller to accommodate the important organ.

If it loses 5% of its weight in water, you will start to get dizzy and could potentially faint. A 10% loss will result in extreme dehydration and possible death.

Most people can move both of them at once, but not each separately. If you are among the 33% that can move one at a time, consider yourself special. Unfortunately, it’s a talent that probably won’t benefit you much.

We’re speaking in digital camera terms. The resolution of the eye is between 120 to 140 megapixels. Although, the highest resolution is in your central field of vision. Colors and pixels become less defined as you approach the sides of your vision field.

They all do different things ranging from digestion to stopping bleeding. Without enzymes, the body would cease to function. They even help you to breathe.

If you let your hair grow out forever and lined all of the hairs up, they would stretch over 450 miles. For most people, each strand of hair grows about half an inch per month.

They are so similar that it is potentially possible to do a cornea transplant from a shark to a human. It could be one of the approved transplant options in the future as technology continues to develop.

No other animal species sleeps on their backs naturally. Some animals like dogs and cats will occasionally do it when they are very relaxed. However, it largely happens to them by accident.

Studies show that smelling a neutral sweet smell can help people who are trying to lose weight. Whenever you are hungry, just take a whiff from a banana or an apple. It will curb your appetite.

We share 70% of our DNA with the slimy insects. Really, it’s not that surprising. Even humans and pickles have 40% of the same DNA.

They are at the age when everything around them is new. It results in a lot of curiosity and a lot of questions. Every couple of minutes, you can expect a question.

It’s pretty rare to be a lefty. The vast majority of people are born right-handed. However, it is possible to learn to use both hands and become ambidextrous.

That’s right, we aren’t the only species with fingerprints. Koalas have them too. Considering how furry they are, you wouldn’t expect it.

Left-handed people chew their food predominantly with the left side of their mouth. It makes sense. Although, it’s not something we normally think about.

It seems implausible, however, a 1000 meter long cube results in a lot of space. It’s enough to pack in all of the billions of people living on earth. It wouldn’t even be that tight of a squeeze either.

Technically though, it depends on what we consider sleep. This figure is based upon reaching the alpha wave stage of sleep. It’s a very light sleep. It takes significantly longer to enter a deep sleep.

It’s the scientific term and is derived from the belly button’s original source — the umbilical cord. The term belly button is just colloquial. It’s what everyone says.

Teeth are the only part that can’t. Yes, the enamel on teeth can be repaired over time. However, once a tooth has formed a cavity, there is no going back.

It has an amazing amount of stamina. We use it all day for things like eating and speaking. Although, if we are talking about the amount of force exerted, the strongest muscle would be the jaw.

Green eyes are also an indicator of higher pain tolerance. Women with darker eye colors like brown or black are the least tolerant of pain.

That is 336 hours of constant kissing. It’s a lot of smooches. Although spread out over a lifetime, it seems like a pretty reasonable amount.

Chemical information is constantly being sent from one neuron to another. These reactions result in everything we consider human. All of our emotions and feelings are derived from chemicals.

Many people imagine it being bigger. However, the fist is a pretty good size gauge. Most human hearts weigh between 220 and 260 grams.

Everything about them is identical at birth, down to their teeth. Although, their brain and body will likely develop differently over time due to environmental and other external factors.

This number does not increase. In fact, it slowly declines. By the time you turn 25, you’ll be losing about 100,000 brain cells per day.

Watching TV is one of the most mindless things you can do. It burns fewer calories than taking a nap does. It’s a good reason to turn off the box and get to bed early.

They are the flavor receptors on your tongue. Some people actually have as many as 8000 taste buds. We imagine that eating must be really enjoyable for them.

That is a lot of different shades of colors. It’s pretty impressive that the eyes can distinguish between so many. They are one of the most miraculous parts of the human body.

Scientists have calculated a “triangle rule” that plastic surgeons use to get the right proportions. An imaginary triangle is drawn with the AC line being the base of the triangle connecting at the nipples. The top of the triangle is the dimple between the clavicle. Next, divide the length of AC by two and then divide that result by the length of the AB or AC line. The “ideal” breasts would have a ratio between 0.4 and 0.6. If the result is above 0.6, it means the breasts are too high; and if below 0.4 then the breasts are sagging.

Of course, science doesn’t determine beauty, but for doctors it helps them get the right proportions.