Do sharks eat people? Detailed answer

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Do sharks eat people? Detailed answer

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Do sharks eat people?

There are about 150 different types of sharks, but while some of them are quite ferocious, it is surprising that most of them are completely harmless.

Sharks are different from other fish in many ways. For example, other fish have movable covers over their gills, while sharks just have slits in their skin. Their spine is made of cartilage, not bone. Another unusual feature of sharks is their teeth. Instead of regular teeth located in the jawbone, sharks have teeth that are arranged in several rows on the gums. The skin on which the denticles are located slowly grows, the row of teeth wears out and is replaced by another behind it.

The shark's mouth is located on the underside of the head. While under water, the fish eats without changing position. And in order to grab prey on the surface, she has to roll over onto her back.

Sharks range in size from 0,3 to 15 meters in length, as, for example, in the great whale shark. The most common species, they often follow ships and are usually so harmless that even other fish are not afraid of them.

However, there are at least two species of rather dangerous sharks. One of them is the tiger shark. She lives in tropical waters and weighs up to 270 kg. The tiger shark can swallow a sea lion and is known for attacking humans. But the most ferocious of all sharks is the great white shark. The length of some individuals can be 12 meters, and perhaps this is one of the strangest fish. They quite calmly, without hesitation, can eat a person and in one fell swoop, like a tiger shark, swallow a sea lion.

Strangely enough, the largest of the sharks is absolutely harmless. This is a whale shark. It can reach 15 meters in length and weigh 18 tons. Its food consists of tiny organisms known as plankton, its teeth, or denticles, are quite small - only 3 mm in height.

Author: Likum A.

Random interesting fact from the Great Encyclopedia:

Who Invented the Microscope?

The word "microscope" is of Greek origin: the first part means "small", the second - "observer". Hence the "microscope" - an observer of something very small.

It is an instrument used to view tiny objects that are not visible to the naked eye. In general, an object appears larger when brought closer to the eye. But if you bring it closer than 25 cm, it becomes indistinguishable. It is said to be out of focus. If you place a simple convex lens between the eye and the object of observation, it will be brought closer than 25 cm, but still be in focus. This can be compared to using a magnifying glass.

And a simple magnifying glass is the simplest microscope that has been used since ancient times. Therefore, when we talk about the invention of the microscope, we mean the complex design of the microscope. And when we talk about a microscope now, we are talking about just that.

What is a compound microscope? The increase in it occurs at two levels, in two stages. The lenses, called "objectives", produce a primary magnified image. There are also other lenses called "eyepiece" that make it larger. In the established practice, there are several lenses in the objective and eyepiece, but the principle remains the same: image magnification in two stages.

The compound microscope was invented between 1590 and 1610. Although no one knows exactly the name of the inventor, this discovery is attributed to Galileo. Sometimes the Danish scientist Leeuwenhoek is considered the father of the microscope. But this is due to the fact that he owns many discoveries made using a microscope. Leeuwenhoek showed that weevils, fleas and other tiny organisms hatch from an egg, and do not appear from nowhere. He was the first to see such microscopic forms as protozoa (protozoa) and bacteria.

At present, the microscope is very important in science and industry.

Test your knowledge! Did you know...

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