探索世界之生命物語 The Human Body: Life Story 5

They are heart cells, and several million of them working at once is a heartbeat. In this case, it's your head that rules your heart as it's your brain that decides what rate your heart should be beating at. The same part of your brain that's controlling your heart is looking after the outside of you, too. Your body needs to maintain a constant temperature of 37 degrees centigrade and your brain has a range of tricks up its sleeve to do it.

This is skin magnified a thousand times. If you look closely, it's covered in holes. They are the openings of tiny ducts--tubes through which sweat can flow. There are about 65, 000 of them on the palm of your hand alone. If you are getting too hot, your brain switches on your sweat glands. As the sweat evaporates, it will help cool you down. And should your brain decide that staying warm is what's needed, it's got another plan, goose pimples. They trap warm air near to the skin and so keep vital heat in.

so all that is being controlled from here inside your head. And don't think you will get out of all the hard work by nodding off. Even when we are completely relaxed or asleep our brains don't let up. This strange contraption is covered in electrodes picking up part of my own brain's activity. 128 sensors detect tiny signals emitted as my brain cells fire. This is the pattern produced when I'm relaxed. Even without a thought in my head, my brainwaves show I'm busy. The truth is our bodies are always busy. They just don't tell us about it. What we see as the monotony of our daily lives when it seems that nothing ever really happens...

words and expressions

have sth. up one's sleeve暗中已有應急的打算；心 中有妙計 (= keep sth. up one's sleeve)

duct:Anatomy A tubular bodily canal or passage, especially one for carrying a glandular secretion:【解剖學】 管：管狀體內(nèi)通道，尤指運輸腺分泌物的管道：
a tear duct.
淚管

switch on:接通

goose pimples: n.(=goose flesh)小疙瘩

nod off:打盹

let up:v.停止, 中止, 放松

contraption: A mechanical device; a gadget.一種機械裝置；小機件

monotony: Tedious sameness or repetitiousness:毫無變化或單調(diào)的重復：
the monotony of daily routine.
一成不變的例行日常公事