What work does the heart do? Detailed answer

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What work does the heart do? Detailed answer

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What work does the heart do?

It is amazingly functional. For 70 years of life, a heart muscle weighing only 300 g, the size of a fist contracts 3 billion times and pumps 250 million liters of blood through the vascular system.

Author: Mendeleev V.A.

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Can carrots help you see in the dark?

Yes, in general, not really.

Carrots are a good source of vitamin A, a lack of which can lead to night (or "night") blindness, when the eye adapts to darkness very slowly.

The inner shell of the eye (the retina) consists of many light-sensitive cells - the so-called rods and cones. Cones are responsible for detail and color, but need a lot of light to function properly (like a "hard" emulsion). Sticks, on the other hand, do not distinguish color at all, but they require much less light (as a "highly sensitive" emulsion), and therefore they are used for night vision. The sticks contain a light-sensitive substance called rhodopsin, the key element of which is vitamin A.

The easiest way to cure night blindness is to increase the intake of vitamin A, which is most often obtained from carotene. Carotene is found in carrots, but even more so in apricots, dark-leafed vegetables (such as spinach), and blueberries.

Still, improving normal night vision and correcting its shortcomings are two completely different things. Eating carrots in large quantities will not help you see better in the dark, the only result you will achieve is that your skin will turn orange.

During World War II, English ace Captain John Cunningham (1917-2002) was nicknamed "Cat's Eye". His 604 Squadron fought exclusively at night. The British government spread a rumor that he could see in the dark because he ate huge amounts of carrots. This was deliberate misinformation to hide the fact that Cat's Eye Cunningham was actually testing a new (and top secret) airborne radar.

It is unlikely that the Germans believed this fable and immediately pounced on carrots, but it helped convince an entire generation of English children to eat a vegetable whose supply remained stable throughout the war.

It must be admitted that the government overdid it a little with the propaganda of carrots. Carrots have become "a priceless treasure dug up from their native British soil." The 1941 "carrot flan" recipe ("reminiscent of "apricot flan" but delicious in its own way") failed to fool anyone. Carrot jam and marmalade also failed to take its rightful place on the British kitchen table.

But the Portuguese love carrot jam. This led to the fact that in 2002 the European Union transferred carrots to the category of fruits.

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