Is a starfish a fish? No, starfish are not fish. Fish are vertebrate animals that live in the sea, have gills to breathe through, have a two chambered heart, are cold blooded, and have a brain and central nervous system. Starfish live in the sea, but that is where the similarity stops. These days, many […]
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Why is mercury poisonous? It can damage the nervous system, kidneys, liver, and immune systems of people and animals. Mercury is a heavy metal. Heavy metals are metals that are very dense and have a high atomic number. Mercury has an atomic number of 80. It melts at -38.83℃, which means it is liquid at
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Do all liquids expand when they freeze? No. Water is the only liquid that expands when it freezes. There are four states of matter: solid, liquid, gas, and plasma. As almost all substances go from the solid phase to the liquid phase and then to the gas phase, they become less dense. This is all
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How does a helicopter with two rotors work? The rotors rotate in opposite directions and are on a transmission so that they don’t collide with each other There are over twenty different types of helicopter that have two rotors. The Chinook is probably the most famous. It was invented in 1961, but the first tandem-rotor
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Why does a boomerang come back? One wing travels faster than the other which causes it to fly in a circular path. However, not all boomerangs are designed to come back and the one most people are probably thinking of is the modern version of the boomerang. The boomerang was a weapon used by the
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What is a nerve? They are bundles of nerve fibers called axons that connect neurons. They look like cables. Their job is to transmit electrical impulses. All animals have nerves. They are the only way that living organisms can send signals from their brain to their muscles or parts of their bodies. The only animals
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What are rare earth metals? They are a group of 17 elements on the periodic table that are spread out so much in the earth that they are difficult to mine, hence the name “rare”. There are seventeen rare earth elements, and they all have different uses. Here they are with their uses: Yttrium –
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Why aren’t there flying boats anymore? Because landing and takeoff is rough, they are not very stable, engines became more powerful, more runways on land were built, and the sea is very corrosive. Before we start, let’s have a quick look at what a flying boat actually is. You are probably thinking of one of
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Why do British people say football and Americans say soccer? Britain used to call football soccer until about 1980 when they started to call it football. Before we start, this article is about the sport of two teams of eleven people trying to kick a ball into each other’s goal. Not the sport that is
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Are symbiotic relationships always beneficial to both parties? No, they aren’t. There are mutualistic, commensalistic, and parasitic symbiotic relationships. The word symbiosis means “a close, prolonged association between two or more different biological species”. It originates with the Greek word symbiosis and means living together. We tend to think that a symbiotic relationship is beneficial
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