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6METING ENGLISH From bbclearningenglish.com Hello and welcome to 6 Minute English, I'm Alice.
And I'm Neil and I feel terrible.
You look terrible, Neil, if you don't mind me saying so.
Ahh, it's because I had to get up really early this morning.
Oh dear, what time did you have to get up?
8 o'clock.
Oh, Neil, that isn't early.
I get up at 6 every day.
It's so peaceful early in the morning.
Hmm, well, some people are morning people and others.
Oh dear.
Yes, well, today we are talking about the biological reason for this.
It's all about circadian rhythms.
They're produced by a so-called body clock in our brains that regulates our body functions.
Our body temperature, sleepiness and alertness,
hunger and hormone levels.
Plants, animals and many microbes have circadian rhythms.
You know a lot about circadian rhythms.