Jenna wondered what all of the caffeine she drank was doing to her brain. Sally told her that was why she avoided all unnecessary chemicals, and caffeine was unnecessary. Alex said it depends on your definition of necessary. He followed up with “But what does caffeine do in the brain?”
The group began sifting through the websites they found while discussing the effects of caffeine that they noticed. “Well, for me, the main effect is that it keeps me alert. I don’t feel sleepy even when studying late if I’m drinking my coffee,” said Jenna.
“Yeah,” Alex interjected, “but too much and you get jittery. My hands start to shake and I can’t sit still. Does that ever happen to you?”
Sally sniffed in a superior way, but remained quiet.
“Yes, it does” Jenna agreed. “Does anyone see anything about the effects of caffeine on neurons on these websites?”
Sally looked up from her computer and asked “Has anyone ever heard of adenosine receptors? Adenosine seems to have something to do with sleep.”
“Hey, no fair coming up with new types of receptors,” Alex said. “And doesn’t adenosine have something to do with ATP? How can it have receptors?”
“ATP stands for Adenosine Triphosphate,” Sally reminded him.
“The energy source for the cell” they all chorused together, laughing at the memory of their studying together in their first biology course.
“Maybe adenosine gets to go out without its triphosphate. I’ll look it up in my neurobiology book.” Sally pulled her book out of her sack. “There are four types of adenosine receptors,” she reported. “They are G-protein coupled receptors. According to this book, caffeine seems to be an antagonist for these receptors.”
Originally published at http://www.sciencecases.org/caffeine/caffeine2.asp
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