How do plant roots know where water is? Plant roots find water through a process called hydrotropism, which is where they can sense the moisture content of the soil. Not all plants have roots, but the majority do. Mosses and liverworts don’t have roots. They have tiny hairs that they use to hold themselves in […]
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Why do we get sleepy after eating? We get sleepy after eating because digestion, hormones, and our body clock can all reduce alertness, especially after a large meal. A lot of people notice that after a large lunch it becomes very difficult to stay awake through the afternoon, and the coffee starts to look more
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Why do we get a falling feeling in our stomachs when we drop on a roller coaster? The falling feeling we get in our stomachs on a roller coaster happens because some of the organs in our abdomen, especially the stomach and intestines, are more free to shift than organs that are more firmly supported.
#1655 Why do we get a falling feeling in our stomachs when we drop on a roller coaster? Read More »
Why don’t figure skaters get dizzy when they spin? Figure skaters do get dizzy when they spin, but they learn to manage it because they have trained their brains and vestibular systems to cope with the sensation. The sensation of dizziness comes about because of the way our balance system works. There are three parts
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What makes us hungry or full? Hunger is driven by signals such as ghrelin, while fullness comes from a mix of stomach expansion, nerve signals, and hormones released by the digestive system. Ghrelin is known as the “hunger hormone” because it is released when the stomach is getting empty and it is one of the
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How does a laxative work? There are several different types of laxative, and they all work in different ways. Some add bulk to the stool, some soften it by helping it hold more water, some lubricate it, some pull water into the bowel, and some stimulate the nerves and muscles in the intestine. There are
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Why do insects have such short lives? Many insects seem to have short lives because they have evolved to prioritize rapid reproduction over a long life. However, it only seems that way if we focus on certain kinds of insects, or if we only look at their adult stage. Not all insects have short lives.
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Why don’t we notice when we blink? We don’t notice when we blink because our brain suppresses its visual center and makes sure our eyes are pointing in the same direction. Everybody is different, and we all blink a different number of times depending on the time of day, the condition of our eyes, the
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How does muscle memory work? Muscle memory works because the brain makes more efficient connections between neurons. We call it muscle memory because it feels like our muscles are working on their own, but the memory is down to the brain and the nervous system. The more you repeat an action, such as learning to
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How do we make blood? Blood is made in our red bone marrow in a process called hematopoiesis. People have different quantities of blood depending on their size, but it is usually about 8% of a person’s body weight. 55% of the blood is made up of plasma, and the other 45% is a combination
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