10 answers to strange questions that everyone has asked at least once

There are some questions that lie somewhere in the back of our consciousness all our lives, but we do not have an answer to them. You may wonder why something is built in this way, why this particular thing is in this place, or how your body does something. Nevertheless, you do not find answers to these questions, although you know that they should be.

Here you will find 10 questions that people ask every day, and finally get simple answers.

1. Why is smoking prohibited on airplanes?

Smoking on airplanes is prohibited by almost all airlines in the world. In addition to the fact that cigarette smoke is unpleasant to other passengers, smoking can also cause a fire, which probably happened on Varig Flight 820.

Despite the fact that smoking is prohibited, it's hard not to notice that there are ashtrays in the toilets of the plane. And not only in old models, even brand new aircraft are equipped with them.

The answer is that the presence of ashtrays in airplanes is an official requirement of the Federal Aviation Administration for airlines. Even though smoking is prohibited and a fire alarm is installed on the plane, the FAA knows that some people will still smoke. Providing people with a place where they can safely dispose of cigarette butts was considered very important for safety reasons.

2. Why are there blank pages in books?

Many books are often published with one or two blank pages, sometimes even more. In books published in Europe or America, on these pages you can find the inscription "This page has been intentionally left blank" ("This page has been intentionally left blank").

These blank pages are not the result of purposeful waste of paper by publishers, but rather the usual consequence of the printing process. Pages for books are usually printed on very large sheets of paper, rather than on separate format sheets. The machines fold and cut the paper into pages, but the whole work may not be exactly divided into eight, so blank pages may remain after printing.

Sometimes these pages are left for notes, about which there is a corresponding inscription or other message, so that readers do not think that this is a printing error.

3. Why do people sneeze when they look at bright lights?

About a third of all people sneeze uncontrollably when they go out to a brightly lit space, for example, if they go outside from a dark building. This is a phenomenon that has baffled scientists for thousands of years.

Sneezing is a response. It can be caused by a variety of reasons, but most often occurs due to irritation of the nose. However, in the case of the so-called light sneezing reflex, sneezing occurs when looking directly at the light source. Scientists offer a variety of theories to explain why this happens, although none of them has been universally accepted.

Now most scientists believe that the light sneezing reflex may be the result of some intersection of nerves in the brain. The optic nerve that perceives light is located next to the trigeminal nerve that controls sneezing. When the optic nerve sends electrical impulses to the brain, the signal touches the trigeminal nerve, causing the brain to believe that the nose has been irritated and needs to sneeze urgently.

4. Why does hair turn gray?

With age, it happens to everyone. From about the age of 30 (although it may start earlier), people begin to notice that their hair gradually loses its natural color, instead becoming first gray, and then completely white. Despite the widespread occurrence of this phenomenon, its scientific explanation is not so widely known.

Hair gets its natural color thanks to pigment cells called melanocytes. Melanocytes produce chemicals that transmit black, dark brown, red and yellow melanin to the cells that create the main ingredient of hair - keratin. When people age, melanocytes are destroyed, which is why keratin gets less pigment - because of this, the hair turns gray. Eventually, the cells cease to function at all, and the hair ceases to receive pigment at all, becoming completely white.

5. Why are you blown with air when entering the store?

Quite often, when entering a store or shopping center, customers are greeted by a jet of air. The reason is not that the owners want to cool you down. This happens in various types of buildings, including restaurants, factories, and loading bays. There are several applications for this, but the main thing is to maintain the same temperature in the building, preventing the penetration and release of air. The air jet is used to maintain warm air in the store in winter and cold in summer. This is especially useful if the doors have to be kept open all the time. It also helps perfectly against the penetration of insects and debris from the entrance to the building due to the turbulent air that they cannot overcome.

6. What causes butterflies in your stomach?

Every person reading this will at some point in their life experience a feeling known as "butterflies in the stomach". The feeling of trembling in the intestines can occur for various reasons, from feelings of fear and worries about the upcoming event to excitement before the first date. Different emotions can cause sensations and physical changes in your stomach due to the so-called intestinal-brain axis.

The brain interprets feelings such as fear and excitement as stress, and responds to it. It releases additional adrenaline into the body to help us cope with the threat or escape from it, increasing blood flow to the heart, lungs and muscles. Since the amount of blood in the human body is limited, its outflow from other organs, such as the intestines, leads to a familiar feeling of nausea.

7. Why does medical alcohol sting?

People have been using medical alcohol to wash wounds and cuts for a long time. If you've ever used it, you know that it stings when it hits the wound, sometimes even more than the cut itself hurts. This is not because alcohol kills bacteria, but because of the reaction it causes in the body.

When medical alcohol gets on the cut, it acts directly on the VR1 receptors in the skin. These receptors are responsible for the perception of heat. While they are activated at high temperatures, alcohol lowers their threshold to a level at which body temperature is sufficient to activate them. The receptors "seem" that the body is on fire, and they transmit a pain signal to the brain, even though the skin has not been damaged.

8. Why does orange juice taste disgusting after brushing your teeth?

Eating or drinking immediately after brushing your teeth is not such a pleasant experience. Toothpaste can make any taste worse. However, when you immediately after brushing your teeth drink a glass of orange juice in one gulp, you may encounter one of the most disgusting tastes in your life.

It turns out that the unattractive taste is caused by the foaming agent used in most toothpastes. Sodium lauryl sulfate weakens the taste buds responsible for sweets. This means that orange juice and everything else that you eat or drink immediately after brushing your teeth will not be sweet.

In addition, sodium lauryl sulfate destroys phospholipids, which usually prevent bitterness from being too strong. Therefore, toothpaste not only drowns out the sweetness of orange juice, but also enhances its bitterness. Both of these effects create a disgusting taste.

9. Why is the sky blue?

Apart from cloudy days, as well as sunrises and sunsets, the sky is usually blue. This is due to the way some things manipulate light. Just as light passing through a prism creates a rainbow and a mirror can reflect light back to where it came from, many things can scatter light. White light from the Sun hits oxygen and nitrogen molecules, which make up most of the Earth's atmosphere, and scatters, creating colors. However, since the wavelength of the blue color is shorter than the others, it scatters more strongly.

This effect also explains where other colors come from in the sky. Closer to the horizon, the sky becomes much paler because the light passes through more air and dissipates more intensely, mixing with other colors and losing its blue hue. When the sun goes down, as at sunset, the light has to pass through even more air. It diffuses the blue color, allowing red and yellow to penetrate.

10. Why is it so difficult to remember dreams?

Each of us has woken up at least once in our lives after a delightful dream and struggled to remember it just a moment later. It may infuriate you, but even with the use of various self-help techniques, dreams are usually remembered only for a few minutes.

Scientists have suggested several reasons why dreams are so difficult to reproduce in memory. The conditions in which the brain is located during the rem sleep phase, when dreams most often occur, do not allow them to be transferred to long-term memory. The absence of the hormone norepinephrine also plays a role here: this hormone plays an important role for memory and is absent during sleep.

Another factor that contributes to poor memory of dreams is that during REM sleep, the hippocampal neurons cannot work the same way they do in other cases. This in turn causes a misfire in the work of other neurons that help to record memory, which is why dreams disappear so quickly.