1290 questions and answers in this section
Explain why do nocturnal flowers often release a stronger fragrance?

Explain why do nocturnal flowers often release a stronger fragrance?

At night, while we sleep peacefully, the activity of nocturnal insects and other pollinators is in full swing. Moths, a kind of small night butterfly, bats, and...

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Explain why does the Moon move at different speeds in the sky?

Explain why does the Moon move at different speeds in the sky?

The Moon takes about 27.3 days to complete one full orbit around the Earth: this is called the sidereal revolution. But be careful, to return...

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Explain why can frogs breathe through their skin?

Explain why can frogs breathe through their skin?

The skin of frogs is very thin, soft, and especially equipped with numerous small blood vessels just beneath its surface. It has an outer layer, the epidermis,...

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Explain why can lichens grow on inhospitable surfaces?

Explain why can lichens grow on inhospitable surfaces?

Lichen is a winning team composed of a fungus and an alga or a cyanobacterium. In this duo, each does what it does best. The...

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Explain why gravity is weaker in certain places on Earth?

Explain why gravity is weaker in certain places on Earth?

Our planet is not a perfect sphere: it is more like a slightly squashed ball at the poles. This phenomenon, called flattening, comes from the...

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Explain why tempered glass is more resistant than ordinary glass?

Explain why tempered glass is more resistant than ordinary glass?

Tempered glass is ordinary glass subjected to a specific thermal treatment. First, the glass is heated to a very high temperature (around 650 to 700°C)...

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Explain why are glaciers so fragile in Arctic regions?

Explain why are glaciers so fragile in Arctic regions?

Arctic glaciers are very sensitive to changes in the climate. Even a tiny warming is enough to trigger accelerated melting. These enormous masses of ice...

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Explain why does foam form when pouring beer?

Explain why does foam form when pouring beer?

When you pour a beer, you violently mix carbon dioxide (CO₂) with the beer, which had been quietly waiting in the pressurized bottle. The CO₂, suddenly released,...

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Explain why does mustard sting?

Explain why does mustard sting?

What makes mustard pungent is primarily a molecule called allyl isothiocyanate. Initially, mustard seeds contain two substances quietly sitting in their corner: a molecule called...

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Explain why are the volcanoes in Iceland closely monitored?

Explain why are the volcanoes in Iceland closely monitored?

Icelandic volcanoes pose a real threat to the local population and even to other European countries. The main risk comes from volcanic ash, which can...

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