Mr. Jenkins' Students "Digest" Information In New Unit
by Gabe Jenkins
October 09, 2006
My classes followed up the remarkably successful unit on muscles by taking a close look at how their bodies break down & absorb nutrients from the food they eat, and then eliminate their waste. As part of the unit, there were some interesting demonstrations, including some Saltine crackers, some sugar cubes, and a highly memorable day in which we looked at how the large intestine functions (some students "will never look at Raisin Bran the same way again").
In this unit, which also included a mini-unit on nutrients and nutrition, students learned exactly how their bodies digest food:
- Teeth mechanically break down food in the mouth to begin the digestive process;
- Saliva in the mouth further aids the breakdown of certain foods (most notably carbohydrates);
- After food is swallowed, it passes by the epiglottis and into the esophagus, where peristalsis squeezes food downward towards the stomach;
- In the stomach, the churning action of the stomach muscles pulls food apart, a process aided by the secretion of stomach acids, which further break food down into a liquid;
- At this point, food passes into the small intestine, where bile breaks down fats, and the tiny villi throughout the 6 meter-long small intestine absorb the nutrients from the food as it passes;
- Next, the food is pushed into the large intestine, where water is sucked out of the food, and into the bloodstream;
- Last, the rectum forms the digested food into a compact shape, and the wastes are released.
Students showed their creativity in communicating all that they had learned by creating fictionalized comic strip stories depicting the experiences of imaginary food characters, as those characters were processed by a human digestive system. They're pretty interesting, to say the least: anybody who is interested should come by and check them out.
