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How does a snake swallow its prey?

Snakes catch live animals and eat them whole. They can swallow prey several times larger than their head. This is made possible by very loosely jointed jaws which enable the mouth to be opened wide. Backward pointing teeth grip the prey while the mouth is worked over the animal. Lots of saliva helps the meal to slip down the snake’s …

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How does a sea cucumber avoid attack?

Sea cucumbers are echinoderms that have a tough leathery skin rather than a spiny one. Lying around on the sea floor in tropical and subtropical countries they look rather like long fat sausages with tentacles at one end. They feed by poking the sticky tentacles around and then placing them one by one into the mouth. All the food fragments …

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How does a Nuclear Bomb differ from a Conventional Bomb?

Every now and then we hear of countries of the world carrying out heated discussions about nuclear bombs. The topics range from who has the right to own a nuclear bomb and who does not, who should use it and who must not and so on. But what exactly happens when such a bomb actually explodes? And how are nuclear …

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How does a mobile tracker work?

Mobile phone tracking relies on the use of triangulation – taking signal strengths registered from the mobile phone at a minimum of three nearby GSM receiver masts. As the mobile phone companies know the position of each mast, and can tell the signal strength of your phone at each of these nearby masts, they can use this to calculate the …

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How does a mirage trick the eye?

A mirage is a kind of optical illusion that occurs in hot, still weather. A pool of water suddenly appears in the distance. But on approaching, it seems to evaporate and there’s actually no water at all. You may see these mirages on roads in summer. They also occur in deserts, sometimes complete with trees, and may trick a thirsty …

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