Watch on YouTube How do facial expressions work? There are 20 muscles in the face that can be moved in different combinations. There are two kinds of facial expressions: voluntary and involuntary. A lot of study has gone into reading facial expressions and there are many theories about whether they reveal inner thinking or not. […]
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Watch on YouTube Why does blood show up under UV light? Because it absorbs all of the light and appears completely black. When we watch crime movies, the police often use a black light to show stains at the murder scene. Well, a black light will make many bodily fluids glow, but it won’t make
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Watch on YouTube Why do stick insects look like plants? They have evolved to resemble the plants they live and feed on, in order not to be eaten by birds and other animals. Stick insects are a wonderful example of natural selection at work. There are over 6,000 species of stick insect in the world,
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Watch on YouTube How quickly do bones biodegrade? It depends on what kind of soil they are buried in, but from 6 years to thousands of years. The bones we have of dinosaurs are not actually bones but fossils. If a dinosaur dies in the right conditions, minerals can replace the calcium in the bones,
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Watch on YouTube Why is carbon-based life common? Because carbon can bond with many different elements to allow chemical reactions to happen. On our planet all living things contain carbon. There may be lifeforms on other planets that are made of different elements but on Earth, everything uses carbon in one way or another. Plants,
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Watch this on YouTube How do spiders make webs? By producing silk from their bodies and weaving it into a strong web. There are two parts to this question: how do spiders produce silk and how do they make their webs. Let’s look at how they make silk first. Spiders are able to produce silk
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How does cacao become chocolate? Through fermentation, drying, roasting, grinding, and adding milk and sugar. Cacao beans grow on a cacao tree, which is native to the Amazon basin in South America. The tree is called “Theobroma cacao.” “Theobroma” means “food of the gods” in Greek and “cacao” is the Spanish form of “kakaw” and
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Why do some trees make rubber? It protects the trees against pests and helps them heal when they are injured. Rubber is not what comes out of the tree or plant. The liquid that is tapped out of the tree is called latex and it has to be refined before it can be used as
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What is botulism? Botulism is an illness caused by a toxin that the Clostridium botulinum bacteria produces. Clostridium botulinum is a very strong bacteria. They are usually found in the soil in spore form, but they grow very rapidly on the surface of fruit, vegetables, seafood, meat, and any kind of food. They like a
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What is the immortal hydra? It is a tiny, freshwater creature that doesn’t appear to age. Hydra are very small invertebrates that live in freshwater ponds, lakes, streams, and rivers. They are about 10 mm long and have a tubular body. At one end of their body they have a mouth surrounded by twelve thin
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