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Reader's Bank_Level 8_Unit 09                                    Reading Text

Poop may seem dirty or unpleasant, but it is actually useful in many ways. Both animals and people can benefit from it. In nature, some animals rely on poop to survive. Dung beetles eat the plant bits that elephants don’t digest. They also lay their eggs inside the poop. Some birds peck at their own waste to get more nutrients. Wild rabbits eat their poop to absorb leftover nutrients. For these animals, poop is not just waste; it helps them live. Humans are also finding new ways to use waste. Scientists are studying how to turn poop into sustainable energy. One idea is a waterless toilet system. It dries the waste and removes the smell. Then tiny microbes break it down into carbon dioxide and methane. The carbon dioxide helps grow algae for biofuel, and the methane can be used to heat homes. Although often dismissed as waste, poop holds surprising value in both nature and science.

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Your brain has its own special way of getting you to sleep. As the day gets darker, your eyes send a signal to your brain, which begins to produce a hormone called melatonin. The melatonin makes you sleepy, and soon it’s bedtime. Then, as a new day dawns, and your eyes see light again, your brain stops making melatonin. Your body wakes up, and it’s time to start the day.

Our natural supply of melatonin plays a big part in regulating our internal clock, which affects our sleeping and waking cycles. Darkness stimulates its natural release while light suppresses it. In addition to regulating our sleep cycle, melatonin affects our immune system. If we suffer from loss of sleep due to a melatonin shortage, it will weaken our immune system, so we will get sick easily. How can we make more melatonin in our bodies? Turn off all lights and electronics while sleeping so that your body won’t misread it as sunlight. The less light there is in your surroundings, the more melatonin your body produces.

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Owning stocks is like having a few trees in a big forest. After you buy them, you must be patient until they bear fruit. Some people try to make quick money by buying and selling stocks every day. However, studies show that 80% of these short-term traders lose most of their money in the first year. Smart investors, however, choose strong companies and keep their stocks for many years.

A great choice for beginners who want to invest for a long time is an ETF. Unlike individual stocks, which represent just one company, ETFs combine many stocks from hundreds of companies. This mix helps lower risk. It’s unlikely that every company in the ETF will perform badly at the same time. Even in a bad market, some may still do well and help balance the losses. Good examples of ETFs are QQQ, which includes 100 big tech companies like Apple and Amazon, and the S&P 500, which covers the top 500 companies in the U.S. Both have had average yearly returns of 10 to 16%. Investing early could help you grow a nice amount of money by the time you finish college!