mr. turkey sandwich's wild ride

This was actually done for a Biology lab last week, entitled "What happened to the food I just ate?" when we were learning all about the digestive system. I was to write a story detailing the journey of food from going in to coming out. ;) I'm very pleased with how it turned out. Now, you all know me, I'm a gabber. This lab ended up being 5 pages--4 of it my story--so it's long. But it's semi entertaining, so if you have a few minutes, take a peek at the following. You might learn something.

PS: I got 80 out of 80 on this. Yay!

Mr. Turkey Sandwich's Wild Ride

There I was, just minding my own business, like a good turkey sandwich is supposed to do. It’s not like I had anything special on my plate that day (err, other than me), but you know, I was chillin’ in the fridge, happy, nicely put together, you know, the day had potential. And then whammo, what do you know, I’m taken out of my cold happy home and consumed, bite by bite. From there, I went on quite a roller coaster that I will from here on out refer to as Mr. Turkey Sandwich’s Wild Ride.

I was born and raised in a nice little kitchen in AZ. I was made of whole wheat bread, mayo (the real stuff, none of this namby pamby Miracle Whip crap—IT’S NOT MAYONNAISE! Am I right?) turkey meat—white meat only—and the ever important cranberry sauce. Without it, I am one boring sandwich. But with that fruity sugary concoction, I am now special. Complete. I do shows 2 nights a week at a club downtown. All due to cranberry, which I’ve heard, is the world’s most perfect fruit.

Anyway, my day was rudely interrupted when I was put into a mouth and started to get ingested, consumed, nay, brutally torn apart and digested! What rude awakening is this? What had I done to cause such biting and chomping, grinding, and gnashing of teeth?! Immediately I noticed that the tongue was tossing me about, moving my precious food molecules from the front of the mouth, to the top palate, to the back where those molars made my parts unrecognizable. I noticed that the salivary glands produced saliva which contained the digestive enzyme salivary amylase which made it easier for my parts to break down. That salivary amylase. Always so pushy with its hydrolyzing this starch and breaking down that polymer into monomers. He always was a bully. This mechanical and chemical digestion was the initial parting of ways between my bread, turkey, mayo, and cranberry sauce.

My whole wheat goodness, also known as carbohydrates, started to break down from polysaccharides into monosaccharaides, or simple sugars. In this case, glucose. Mayonnaise, or the fat, was unrecognizable at this point and was being broken down into lipids. The turkey, the protein hero of our story, started to break down into amino acids. And the ever faithful sauce d’cranberry, made originally of a delightful fruit and sugar blend, was being broken down into other kinds of carbohydrates, at this point, glucose and fructose.

The whole process happened very quickly and within 20-30 seconds, the first carnivorous bite was made into the shape of a bolus (or, ball o’ food), on its way to the back of the throat and into the pharynx. This is when I started to hear that click click click of the amusement park ride when you’re thinking “wait a minute…is it too late to get off?” There was no going back now. At least, not unless something went wrong. The pharynx evidently leads to either the trachea or the esophagus which then leads to the stomach.

I’ve heard stories of other meals-gone-wrong where the food molecules, for whatever reason, took that left turn at Albuquerque and headed down the trachea/windpipe instead of down the esophagus where it was supposed to go. In those cases, the larynx gets obstructed and sometimes, drastic measures need to be taken. One way to stop that crazy ride is to perform the Heimlich maneuver which compresses the lung and expels the chunk of food from the wrong tube. Fortunately, I was on the right track, the epiglottis steered my food the right way and I went screaming down the esophagus by way of muscle contraction, or peristalsis. OK, it sounds a lot more fun than it was…it was actually quite slow and deliberate. The rhythmic waves of muscle contractions forced my former turkey sandwich self down a deep dark tube towards the stomach of the unknown and beyond.

I waited in nervous anticipation. What would greet me there? Mashed potatoes turn starchy molecules? Gravy recognizable now only as fat? Grandma’s apple pie which looked so good out there was bound to look a bit scary in here. As I was contemplating my bleak future, I suddenly passed through what I brilliantly detected as the esophageal sphincter. Cuz turkey sandwiches are smart like that. That sphincter is a muscle that pretty much kept me from returning back up the esophagus and back into the light.

I passed through the sphincter (there’s a phrase I never thought I’d say) and dropped without warning into a churning organ, complete with digestive fluid known as gastric juices secreted by the cells lining the stomach’s interior. It was a scary scary place, my friend. The walls were moving in and out; the goop I landed in was made of strong acid, digestive enzymes called pepsins, and mucus of all things. 3 things I had specifically not ordered for my next spa treatment. Pepsin was breaking down the polypeptides of protein from my turkey down into even smaller pieces. On the lining of this massive organ, I saw a peptic ulcer caused by bacteria. In my wisdom I knew that this occurred because the lining of the stomach was eroding faster than the new cells could regenerate, which happens every 3 days or so. The bacteria’s metabolism was damaging the mucus coat lining the stomach, making it a target for gastric juice. That gastric juice, he must hang out with salivary amylase: just a couple of bullies breaking down food particles for fun.

As the gastric juices had their way with my precious poultry parts, I was torn down into more and more basic molecules that came together in a nice slimy concoction known as acid chime. What every good turkey sandwich aspires to be, right? The muscles in the stomach transferred the chime a squirt at a time (sooo appetizing, turkey sandwich anyone?) to the small intestine. It takes the stomach between 2 and 6 hours to completely empty. But I was on such a terrifying horror roller coaster in the gastric juice glop that I was ready to move on.

OK, the small intestine. 6 meters is really a long slow way to travel when you’re not quite feeling yourself. Forget airport stink, this was something that made me rethink my Aruba vacation plans next spring in favor of staying closer to home and away from any oral orifice anywhere. Acid, enzymes, and mucus are not happy travel companions either. They’re all about the “let’s break this down” and “see what we can do to that molecule” and “that polymer is way too big.” I was like “take a breather, boys, let’s enjoy the sights of the small intestine.” But they weren’t having it. It’s like they were contracted to do what they do under some higher power. This is actually where I started saying goodbye to pieces of my former self, never to see them again. Because at this point, some of my nutrients were actually absorbed into the bloodstream. I was now, technically, inside the body. Hydrolases continued to break down all my food macromolecules into monomers, mixed with that ever-fun-loving acid chyme.

1 foot into the small intestine I came upon the duodenum, which is a really funny word and fun to say out loud in different accents. We turkey sandwiches do that kind of thing just for kicks, you know, to pass the time. This duodenum receives digestive juices from the pancreas, liver, and gall bladder. Now, that’s a lot going on right there, so let’s take a closer look. I saw that pancreas secrete pancreatic juice into the duodenum through a duct, helping to neutralize some of that icky stomach acid which was giving us all fits. To get technical, epithelial cells in pancreatic ducts secrete pancreatic bicarbonate. Its hydrolases continued to chemically digest my carbs, fat, proteins, and any nucleic acids that also found their way in this deep dark pit of despair. The liver was producing its own freaky fun fluid, otherwise known as bile. The bile was then stored in the gall bladder, a teeny tiny little place, and then secreted through another duct to join the pancreatic juice in the duodenum. The bile’s job (and it did it so well, it had won the Disgusting Fluid of the Month award several months running—the mucus is totally jealous) was to create salts that would bind to the droplets of fat produced from larger globules in the muscles in the intestinal wall. The salts stopped the fat from reforming into large globules and wreaking havoc everywhere they went. Those fat globules seriously need a talking to. They’re out of control.

‘Bout this time my sandwich-formerly-known-as-turkey self was getting tired and I really wanted to look for a hotel to crash for the night. But the hydrolases were like slave drivers and would not have any resting on their watch. They continued to break down all the food molecules down even smaller, getting us ready for absorption into the body. I went careening through the rest of the small intestine, through the jejunum and ileum (two more really great funny words when pronounced with a southern accent). The villi and microvilli outgrowths on the intestinal lining helped transport my nutrients into the network of small blood vessels and lymphatic vessels in the core of each villus. The bloodstream then carried all my loved ones away to distant lands in distant cells. The rest of me continued on to the dark cold world of the large intestine.

The large intestine also goes by the street name of colon. It’s shorter there but much wider. Another sphincter controls what is now left of my once delightful ensemble. Here, water is absorbed and taken back into the body. The undigested parts of me become more solid. Surely, a more peaceful future lies ahead? After going through the disturbing and startling turns of the upper gastrointestinal tract (including the mouth, pharynx, esophagus, and stomach,), the lower gastrointestinal tract (including the small intestine, large intestine, and anus) had to be a bit of a smoother ride, right? One thing that really ruined my day is that what was formerly a nice sandwich made from leftover Thanksgiving goodness was now pretty much known as crap. Well, feces, specifically. Mainly, indigestible fibers, some intestinal prokaryotes along for the ride, bacteria, and a right jolly group of folks on their way out of this body and off this crazy ride.

The last 6 inches of this trip, I found myself in the rectum, where all the feces is stored until eliminated. Let go. Sent home. Evacuated. Kicked off the island. Dropped off at the pool. You get the picture. The colon started to contract and two more of those busy sphincters regulated opening of the anus and what was left of me exited Mr. Turkey Sandwich’s Wild Ride.