What is chewing gum made of and what happens if you swallow it? These days, chewing gum is just a gum base with sweeteners and a plasticizer. You can swallow it without any harmful effects. Humans have used something to chew on for thousands of years. A 5,000-year-old lunch of birch bark tar with toothmarks […]
#384 What is chewing gum made of and what happens if you swallow it? Read More »
Why does a chicken’s head stay perfectly still when you move its body around? Because chickens cannot move their eyeballs in their eye socket and because they don’t have a vestibulo-ocular reflex. Our heads (humans) are pretty much constantly moving, yet we can see perfectly well. This is all thanks to the vestibulo-ocular reflex which
#374 Why does a chicken’s head stay perfectly still when you move its body around? Read More »
How much maple tree sap do you need to make 1 liter of maple syrup? It takes about 40 liters of sap to make 1 liter of maple syrup. Maple syrup is made by taking the sap from sugar maple, black maple, or red maple trees. The trees are tapped when they are about 30
#368 How much maple tree sap do you need to make 1 liter of maple syrup? Read More »
Why are steam burns worse than boiling water burns? Steam burns are more severe than boiling water burns because steam goes through a phase change when it touches your skin, and it can penetrate your pores. Water is made up of molecules and molecules are made up of atoms. These atoms each have electrons and
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Why do people have different blood types? Scientists don’t know why humans have different blood types, but a good hypothesis is that they protect us as a species against different diseases. We have approximately 4.5 to 6 liters of blood, depending on our size. Blood is generally about 10% of our body weight. Blood is
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Why can we eat lettuce and spinach, but we can’t eat leaves and grass? We can’t eat leaves and grass because of the cellulose and silica they contain. There are several different ways of getting energy. Plants photosynthesize and make energy, which they store in their cells. Herbivores eat the plants to get the energy
#362 Why can we eat lettuce and spinach, but we can’t eat leaves and grass? Read More »
How does antibiotic resistance happen? Bacteria develop the ability to survive an antibiotic, which is then passed on to future generations. The antibacterial power of some moulds has been known about since 1874, possibly even earlier. In 1897, Ernest Duchesne published a paper about the ability of moulds to kill bacteria. Alexander Fleming noticed that
#355 How does antibiotic resistance happen? Read More »
How do reflexes work? They work by using a reflex arc that bypasses the brain. There are many different types of reflex, but they are generally meant to protect us and to allow us to move around without having to think about everything. Our brains have a limited amount of processing space and if we
#352 How do reflexes work? Read More »
How do amphibians breathe underwater? They breathe through their skin. The word “amphibian” comes from the Greek amphi, meaning both and bios, meaning life. The word was first used in the 1630s and it was used to mean animals that “have two modes of existence”. There are about 7,000 different types of amphibians in the
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What causes brain damage? There are several things that cause brain damage. These can be traumatic injury, poison, stroke, tumor, or lack of oxygen. The brain weighs about 1.5 kg on average and contains over 100 billion nerve cells. It uses 20% of the body’s energy, which is more than any other organ. Obviously, without
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