You get a new stomach lining every three to four days. The mucus-like cells lining the walls of the stomach would soon dissolve due to the strong digestive acids in your stomach if they weren’t constantly replaced. Those with ulcers know how painful it can be when stomach acid takes its toll on the lining of your stomach.
The surface area of a human lung is equal to a tennis court. In order to more
efficiently oxygenate the blood, the lungs are filled with thousands of branching bronchi and tiny, grape-like alveoli. These are filled with microscopic capillaries which oxygen and carbon dioxide. The large amount of surface area makes it easier for this exchange to take place, and makes sure you stay properly oxygenated at all times.
The human brain cell can hold 5 times as much information as the Encyclopedia Britannica. Or any other encyclopedia for that matter. Scientists have yet to settle on a definitive amount, but the storage capacity of the brain in electronic terms is thought to be between 3 or even 1,000 terabytes. The National Archives of Britain, containing over 900 years of history, only takes up 70 terabytes, making your brain’s memory power pretty darn impressive.
Your brain uses 20% of the oxygen that enters your bloodstream. The brain only makes up about 2% of our body mass, yet consumes more oxygen than any other organ in breathe deep to keep your brain happy and swimming in oxygenated cells.
The brain is much more active at night than during the day. Logically, you would think that all the moving around, complicated calculations and tasks and general interaction we do on a daily basis during our working hours would take a lot more brain power than, say, lying in bed. Turns out, the opposite is true. When you turn off your brain turns on. Scientists don’t yet know why this is but you can thank the hard work of your brain while you sleep for all those pleasant dreams.
Scientists say the higher your I.Q. the more you dream. While this may be true, don’t take it as a sign you’re mentally lacking if you can’t recall your dreams. Most of us don’t remember many of our dreams and the average length of most dreams is only 2-3 seconds–barely long enough to register.
Neurons continue to grow throughout human life. For years scientists and doctors thought that brain and neural tissue couldn’t grow or regenerate. While it doesn’t act in the same manner as tissues in many other parts of the body, neurons can and do grow throughout your life, adding a whole new dimension to the study of the brain and the illnesses that affect it.
Information travels at different speeds within different types of neurons. Not all neurons are the same. There are a few different types within the body and transmission along these different kinds can be as slow as 0.5 meters/sec or as fast as 120 meters/sec.
The brain itself cannot feel pain. While the brain might be the pain center when you cut your finger or burn yourself, the brain itself does not have pain receptors and cannot feel pain. That doesn’t mean your head can’t hurt. The brain is surrounded by loads of tissues, nerves and blood vessels that are plenty receptive to pain and can give you a pounding headache
80% of the brain is water. Your brain isn’t the firm, gray mass you’ve seen on TV. Living brain tissue is a squishy, pink and jelly-like organ thanks to the loads of blood and high water content of the tissue. So the next time you’re feeling dehydrated get a drink to keep your brain hydrated.
Hair and Nails
While they’re not a living part of your body, most people spend a good amount of time caring for their hair and nails. The next time you’re heading in for a haircut or manicure, think of these facts.
Facial hair grows faster than any other hair on the body. If you’ve ever had a covering of stubble on your face as you’re clocking out at 5 o’clock you’re probably pretty familiar with this. In fact, if the average man never shaved his beard it would grow to over 30 feet during his lifetime, longer than a killer whale.
Every day the average person loses 60-100 strands of hair. Unless you’re already bald, chances are good that you’re shedding pretty heavily on a daily basis. Your hair loss will vary in accordance with the season, pregnancy, illness, diet and age.
Women’s hair is about half the diameter of men’s hair. While it might sound strange, it shouldn’t come as too much of a surprise that men’s hair should be coarser than that of women. Hair diameter also varies on average between races, making hair plugs on some men look especially obvious.
One human hair can support 3.5 ounces. That’s about the weight of two full size candy bars, and with hundreds of thousands of hairs on the human head, makes the tale of Rapunzel much more plausible.
The fastest growing nail is on the middle finger. And the nail on the middle finger of your dominant hand will grow the fastest of all. Why is not entirely known, but nail growth is related to the length of the finger, with the longest fingers growing nails the fastest and shortest the slowest.
There are as many hairs per square inch on your body as a chimpanzee. Humans are not quite the naked apes that we’re made out to be. We have lots of hair, but on most of us it’s not obvious as a majority of the hairs are too fine or light to be seen.
Blondes have more hair.They’re said to have more fun, and they definitely have more hair. Hair color determines how dense the hair on your head is. The average human has 100,000 hair follicles, each of which is capable of producing 20 individual hairs during a person’s lifetime. Blondes average 146,000 follicles while people with black hair tend to have about 110,000 follicles. Those with brown hair fit the average with 100,000 follicles and redheads have the least dense hair, with about 86,000 follicles.
Fingernails grow nearly 4 times faster than toenails. If you notice that you’re
trimming your fingernails much more frequently than your toenails you’re not just
imagining it. The nails that get the most exposure and are used most frequently grow the fastest. On average, nails on both the toes and fingers grow about one-tenth of an inch each month.
The lifespan of a human hair is 3 to 7 years on average. While you quite a few hairs
each day, your hairs actually have a pretty long life providing they aren’t subject to any trauma. Your hairs will likely get to see several different haircuts, styles, and even possibly decades before they fall out on their own.
You must lose over 50% of your scalp hairs before it is apparent to anyone. You lose
hundreds of hairs a day but you’ll have to lose a lot more before you or anyone else will notice. Half of the hairs on your pretty little head will have to disappear before your impending baldness will become obvious to all those around you.
Human hair is virtually indestructible.Aside from it’s flammability, human hair
decays at such a slow rate that it is practically non-disintegrative. If you’ve ever
wondered how your how clogs up your pipes so quick consider this: hair cannot be
destroyed by cold, change of climate, water, or other natural forces and it is resistant to many kinds of acids and corrosive chemicals.
Though we may not give them much thought unless they’re bothering us, our internal organs are what allow us to go on eating, breathing and walking around. Here are some things to consider the next time you hear your stomach growl.
The largest internal organ is the small intestine. Despite being called the smaller of the two intestines, your small intestine is actually four times as long as the average adult is tall. If it weren’t looped back and forth upon itself it wouldn’t fit inside the abdominal cavity.
The human heart creates enough pressure to squirt blood 30 feet. No wonder you can feel your heartbeat so easily. Pumping blood through your body quickly and efficiently takes quite a bit of pressure resulting in the strong contractions of the heart and the thick walls of the ventricles which push blood to the body.
The acid in your stomach is strong enough to dissolve razorblades. While you
certainly shouldn’t test the fortitude of your stomach by eating a razorblade or any other metal object for that matter, the acids that digest the food you eat aren’t to be taken lightly. Hydrochloric acid, the type found in your stomach, is not only good at dissolving the pizza you had for dinner but can also eat through many types of metal.
The human body is estimated to have 60,000 miles of blood vessels. To put that in
perspective, the distance around the earth is about 25,000 miles, making the distance your blood vessels could travel if laid end to end more than two times around the earth.