True / False Test 10 - The Science of Sleep

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Sleep is a fundamental biological process that is essential for physical and mental well-being. During sleep, the body repairs damaged cells, strengthens the immune system, and consolidates memories. Adults typically need between seven and nine hours of sleep per night, although individual requirements can vary. Teenagers, whose brains are still developing, need approximately eight to ten hours. Sleep occurs in cycles, each lasting about ninety minutes. A complete cycle includes four stages: three stages of non-REM sleep and one stage of REM (Rapid Eye Movement) sleep. During REM sleep, the brain is highly active, and most dreaming occurs. As the night progresses, the periods of REM sleep become longer, which is why people are more likely to remember dreams if they wake up in the early morning. Chronic sleep deprivation has been linked to a wide range of health problems, including obesity, heart disease, depression, and weakened immune function. Research has also shown that even moderate sleep loss can impair cognitive performance as much as alcohol intoxication. Despite this evidence, many people in modern society regularly sacrifice sleep for work, entertainment, or social media.