Science questions for kids | Why do adults need less sleep than children? Do they really need it or are they just fooling around?

Lempi Vehviläinen, 4

It, how much sleep a person needs changes as a person gets older. Usually a person needs more sleep as a child, less as an old person.

A lot of sleep is needed to grow from a child to an adult. For example, at the age of 4, it would be good to sleep at least 11 hours at night and during the day. It is common for a 4-year-old to need up to 14 hours of sleep. As an adult, for example 35 years old, sleep is needed less than as a child, but it would still be good for an adult to sleep about 8 hours every night. So adults are not lying when they say they need less sleep than children.

A good night’s sleep refreshes us. In people of all ages, sleep also helps the brain develop. During sleep, brain cells are cleaned twice as well as when awake. It keeps the brain healthy. In sleep, connections from neurons to other neurons also improve. It keeps the memory good.

However, old people often have illnesses, which is why the need for sleep increases. Then an old person can sleep as long as a child sleeps. However, due to illness, the old person’s sleep is not as refreshing.

Timo Partonen

research professor

Department of Health and Welfare

In some other universe, can 1+1 be something other than 2?

Touko Kemppinen, 11

1+1 there are two everywhere and there have been before. It is easy to illustrate the calculation by, for example, adding another apple to the amount of one apple. In this case, there are two apples.

However, it can be interesting to consider whether talking about numbers is at all connected to the way we humans observe and think.

In recent decades, much research has been done on the mathematical abilities of young infants and other animal species, such as some monkeys, rats, and insects that live in groups.

It has been proven that human babies and many animals process numbers in much the same way as us slightly older humans. However, they can’t write numbers on paper.

However, apparently not all animals understand numbers. We can also imagine a whole world whose inhabitants would not perceive separate things at all.

In that case, they probably wouldn’t have developed an understanding of numbers either.

Juha Oikkonen

professor emeritus of mathematics

university of Helsinki

If you are allergic to cats, are you also allergic to tigers?

Jon Korhonen, 8

Often animals of the same species origin have similar allergens in their skin or saliva. This is also the case with cats and tigers and other “wild cats”.

There has been little scientific research on the topic, but one study found that cat-allergic people also react to many big cats, such as cougar, jaguar and Siberian tiger.

On the other hand, it is the case that not everyone always gets visible allergy symptoms even from ordinary cats, even if they are sensitized to cats according to allergy tests.

So the answer is: with a high probability, a person with a strong cat allergy can also get symptoms from a tiger.

Fortunately, just looking at a tiger does not cause symptoms, but only caring for the animal or other close contact.

Mika Mäkelä

pediatric allergology specialist

Skin and allergy hospital, Hus

Why is the letter r generally difficult to learn?

Kalle Kylmäniemi, 10

The letter R or more correctly, the r sound can be difficult to learn because it is demanding in terms of tongue movement.

All or most of the other Finnish sounds are usually learned before erra. Some learn that sound by themselves by experimenting or from the model of other speakers, but many need help to learn.

You have to be able to raise the tongue in a cup-like manner on the teeth, and the tip of the tongue must be made to vibrate, i.e. make vibrations with the help of the air stream coming from the lungs. The tip of the tongue must be relaxed and on the other hand the edges of the tongue must be pressed against the palate.

Some use, for example, French or American erra instead of Finnish erra.

If the vibrating stutter has not been found by preschool or school age and it is bothersome, you should ask for help from a speech therapist or a special education teacher at school. Errän can be learned even as an adult.

Some people who have challenges with saying something wrong have someone in their immediate family who has had a similar challenge, but this is not always the case.

Katri Saaristo-Helin

university lecturer, speech therapist

university of Helsinki

Send the question, the questioner’s full name and age to [email protected]. The column is edited by Touko Kauppinen and Juha Merimaa.