The Campus Coffee Shop:
Caffeine Conundrums

Part I—Introduction

The rich, strong smell of coffee filled the newest coffee house in the small college town. The place was packed with students sitting at small art deco bistro tables. A hip-looking barista was busy taking customer orders behind the counter while a loud grinding sound purred from the espresso machine, followed by the gurgle of steaming milk. Students were glued to their laptops—coffee in one hand, mouse in the other. Sally, Alex, and Jenna were sitting together at one of the tables, discussing their latest biology project, “Science in Everyday Life.”

Taking a sip from her water bottle, Sally said, “It’s getting late and we still don’t have a topic and this project is due the day after tomorrow! Let’s get moving. We all have classes all day tomorrow and we are running out of time!”

“Don’t worry, Sally,” Alex said, after guzzling down his energy drink. “We’ll definitely get through it, we have plenty of time to finish and I’m not tired whatsoever.”

Jenna, gulping down her third espresso latte of the night, added, “Yeah, Sally, we’ll get through it, you just need some caffeine to keep you awake so we can finish it tonight. It will be the best project Professor Jackson has ever seen.”

“I don’t understand why you both need caffeine. Stress keeps me going,” Sally replied.

“I’m not addicted,” said Jenna. “Coffee just keeps me moving with all the demands of college life. I have at least one cup in the morning, one in the afternoon and two or more while studying in the evening. I’ve been drinking coffee since the first day of my freshman year, and it’s been working great.”

“I usually only need a quick boost every now and then before a deadline,” added Alex.

“That gives me a great idea… why don’t we focus our project on the effects of caffeine on the human body?” interjected Sally.

“Good idea, let’s go with it. Now, where should we start?” replied Alex.

Questions

1. List common foods/drinks that are sources of caffeine. How much caffeine is found in each?
2. What is the chemical structure of caffeine? What class of chemical molecules does caffeine belong to?
3. What are common physiological effects of caffeine consumption?
4. Where in the body does caffeine act?
5. Propose reasons why Alex and Jenna feel the need to consume caffeine while Sally does not. Why does Jenna feel that she needs more caffeine than Alex?

Image credit: Digital image created by B. Rybarczyk, 2005.

Date Posted: 09/28/05 nas.

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