39
(A)They also found that during sleep, the brain’s cells shrink, or become smaller.
(B)While we sleep, our brains are doing much more than getting ready for the next day.
(C)She said the results demonstrate just how important sleep is to health and fighting disease.
(D)The brain expert says our brains perform two very different jobs.

“When we are awake, the brain cells are working very hard at processing all the information about our surroundings. The researchers say that the waste material includes poisons, or toxins, responsible for brain disorders such as Alzheimer’s disease. It is not just beauty sleep. The brain needs us to sleep so it can get to work. 39.They also found that during sleep, the brain’s cells shrink, or become smaller. This shrinking permits waste to be removed more effectively.

Google翻譯：

“當我們醒著時，腦細胞正在非常努力地處理有關我們周圍環境的所有信息。研究人員說，這種浪費的物質包括導致腦部疾病如阿爾茨海默氏病的毒藥或毒素。不僅僅是美麗的睡眠。大腦需要我們睡覺，這樣它才能開始工作。他們還發現，在睡眠過程中，大腦的細胞會縮小或變小。這種收縮允許更有效地去除廢物。

單字字意：

toxin 毒素

shrink 收縮；畏怯；變小；迴避

permit 允許；使...有可能