Snake Biology Lesson

Chapter 1: The Slacker

Brian Mosidi was a slacker. He cut classes and goofed off. Not to the point where he was utterly failing things, but to the point where his grades had rapidly declined and he was in danger of not graduating at the end of the semester, his last one. He had been doing well up till that point but had gotten senioritis and had cut classes, especially his first period biology (due to him goofing around on his motor bike that his parents gave him for his 17th birthday.) Now, however, with a bad report from his classes that came home to his parents, he was given an ultimatum, improve his grades so that he passed every class or else be grounded for months.

And so in the final quarter, he had busted his ass to get his grades up to at least a C, or, at worst, a high D (that was the case for British Literature, a course he was required to take, though he didn't know why). However, his biology grade was in the 40's. Try as he could, even with all the available extra credit, it seemed that, as he approached the third week before the end of the semester, that he would need a 100% on the final exam, which he knew was too high out of his reach, to get a passing grade in the class. It seemed that, barring a miracle, he was going to have to take biology again in the fall, with him being grounded all summer long.

"Dr. Bentenson" he said to his biology teacher, a ferret, "is there any way, any way at all for me to get enough extra credit to pass this class without acing the final exam?"
"I don't see how. Your grades have been pretty low for the first half of the semester."
"Look, I'm gonna get grounded all summer long if I have to repeat this class all over again! I'd be willing to do anything to pass it!
"I don't see how I could justify giving enough extra credit to make up so many percentage points. Not unless....." he broke off, "well, there is one thing you could do. Something I've been working on as a little biology experiment. It's never been tested and, so far, nobody has been willing to volunteer to help trial run it, not even when offered $3000."
"Holy shit, $3000 is a lot of dough. And they still turned it down?! What could it involve?"
"Tell you what, you meet me after school today and I'll tell you. Right now, I've got to start class." he said as students began to file in for the start of class.

Chapter Two: The Proposal

As the final school bell rang, Brian made his way up to the biology classroom. He had to wait around for a student, who arrived first, to finish getting assistance from the instructor. Brian often had come these days after school to seek help as well. But this would be no ordinary tutoring session. As the student left, the ferret beckoned for him to come in. "Take a seat, Brian." he said.

"What did you have in mind? What is this experiment of yours?"

It's a biology experiment. I've developed something that is resistant to acid. This should entail someone, using the suit I developed, to go inside of the stomach of a creature and explore its digestive tract."
"Explore a digestive tract?" Brain asked, not sure if he'd heard correctly.
"Yes, that's right, of the class pet snake, Slybella.". Slybella was a large exotic python.
"So you want the snake to swallow me?"
"Yes, I think that's the best way to explore the digestive tract."

"So you want me to explore her stomach."
"The whole digestive tract actually."
"You mean from her mouth all the way to her anus?"
"Snakes have a cloaca, as you'd know if you paid attention in class."
"What's the difference between an anus and a cloaca?"
"Looks like you're going to find out, at least if you're willing to go through with this."
"Sounds a bit messy, coming out a snake's tailhole."
"Well, it's up to you if you want to do this."
"I don't see that I have much choice, unless I want to fail the class."
"it is a dangerous, you know. I couldn't even get people, when paid, to do it. You could be digested and die."
"Yes, well, being digested seems a less worse fate than being grounded all summer." "Well, if you're set on doing this, then come into my office first thing tomorrow morning. I have some forms for you to sign. Legal matters."
"Ok, I'll see you then.

Chapter 3: Preparing for the Trip

Brain signed the forms. They were liability forms waiving Dr. Bentenson from liability in the event that he didn't survive the trip through the snake. As he was 18, he was old enough to sign legally binding forms. He and Dr. Bentenson had agreed that the best cover story so that Brian's parents wouldn't raise a stink would be to make it sound as it Brian was going on a special field trip for his biology class, in order to get enough extra credit to pass the class. This was, after all, more or less true. This would keep his parents from worrying about him when he didn't show up all week. He already had things set up so that he could make up the work in other classes. Naturally, he'd be getting all automatic 100's for any work in biology class that he'd be missing that week. The extra credit would give him enough so that he could get at least a D in the class while not needing to ace the final. He was set to be swallowed by the snake Monday morning, and it was Thursday now.

Since he would be preoccupied the following week, Brian made sure to do extra recreational activities the rest of that week and the weekend. He also took the time to research a bit on the anatomy of snakes. He found that it took a snake several minutes to send its prey from its mouth to its stomach. A python attacked it prey by trying to crush the life out of them. Thus, he knew he had to pretend to be subdued so that he wouldn't be suffocated or have his ribs cracked. He knew that he'd need food and water for the week that he was inside the snake. Regular food wouldn't do, for it would no doubt spoil without refrigeration, especially in the harsh conditions of a snake's digestive tract. So, of course, he packed lots of junk food. He also packed lots of water, as well as soda. Also, as it would no doubt reek inside a snake's digestive tract, especially at the lower end, he brought along several air fresheners. He also brought along toilet paper, as he wasn't sure if he could go a week without shitting and he'd have to go inside the snake. He also packed a change of clothes (though the suit would protect his clothes, they still would have been worn a week, and inside the hot interior of a snake too), a towel, shampoo, and a bar of soap. He didn't plan to shower inside the snake, but he knew he had to shower and clean off before returning home, as he knew his parents wouldn't be happy if they learned he'd come out the cloaca of a snake smelling like its bodily wastes and so he planned to clean off before going back home. Thankfully, there was a gym men's shower room right next to the biology classroom, so he could covertly sneak in to wash off.

He also had to tell his girlfriend Leona not to contact him. He didn't want her to phone him while he was inside the snake, as that would likely lead to awkward questions if she heard digestive noises throughout the phone call. So he'd said that he was going to a remote area where he wouldn't get service for the field trip, so as to not offend her or arouse suspicion as to his telling her he would be unavailable for that week. Perhaps after this was all over, the two could make love on the following Friday night. They hadn't made love yet, but were getting closer, and having this to look forward to as a reward once the whole snake ordeal was all over made things more bearable.

He also packed a flashlight and a few changes of batteries. He also brought a phone charger with a small portable generator. It would be a shame if he didn't get any shots of the snake's innards and he doubted that his phone would last a week without charging. He had a metal container to place it in when not in use, so that it wouldn't get damaged by the snake's digestive system. Thankfully his phone was waterproof as well, so it wouldn't be harmed by saliva or other things inside the stomach, at least, he hoped that it wouldn't, as it cost about $500 and his parents weren't likely to get him such a nice one again if this one, which he'd only had for a year and a half, got ruined already.

The weekend, in which he enjoyed himself as much as he could, went by quickly. On Sunday night, he went to bed extra early. This was owing to the fact that he knew he wouldn't get quality sleep, if much sleep at all, inside the digestive tract of a snake. As Monday morning dawned, he got up and went through his normal routine He wondered if he was doing the right thing. Sure, he would now pass his class, but that was assuming he survived. What if something went wrong and he died? He'd never get to make love with Leona and he'd never get to own a house or own his own car (he borrowed his parents' car right now) and that would suck. Still, he had faith that his instructor had made his materials correctly so that he wouldn't digest and so he'd be able to breathe inside of the snake. He walked slowly to school, though he could have driven, savoring his time on the outside of the snake. Finally, as it neared the start of class, he entered the classroom.

Chapter 4: Swallowed by the Snake

"Now class" Dr. Bentenson said as the class filed into the room, "we have something special this week. Brian here has agreed to test out an experiment of mine. Of course, I'd like it if nobody told anyone else outside of this class about it. It violates some school rules. But if you can agree not to talk, this whole thing should be educational as well as fun for you all."
"I'm not sure how much fun it will be for me," Brian interjected.
"Yes, but at least you'll pass the class."
"What's going on?" asked Eliza Kinkabu, a mink.
"Brian here has agreed to go through the digestive tract of our class pet snake, Slybella, and give us an account of the snake's digestive tract."
"Cool! We want to see this!"
"I hope Brian gets digested!"
"Won't he be snake poo if he goes all the way through?"
"I promise I won't tell."
"This is gonna be cool! Best week ever in this class!"

"Ok class. Settle down." Dr. Bentenson said. "Before we have Slybella swallow Brian, I think it good to first discuss the swallowing process of snakes and their esophageal anatomy. First, could somehow tell me how a snake can swallow large prey as well as, if you can, how they can breathe while swallowing said prey?"
The anterior portion of the trachea, which resides along the bottom of the mouth/throat, is very strong/mobile and may be extended out of the mouth, beneath the prey being swallowed, to facilitate breathing during ingestion (which, in the case of very large constrictors, is a process that may take over an hour). Snakes tend to have highly kinetic skulls (up to 150 degree opening) for swallowing large prey whole. Most snakes have highly flexible lower jaws (due to the fact the left and right lower jawbones are often not connected) and very stretchable skin, enabling them to effectively wrap their mouths around large prey. Snakes generally eat their prey headfirst. his is because the bodies of most animals are oriented in a head-to-tail fashion, meaning that swallowing prey in that manner will permit everything to go down the snake's throat much smoother. Their forked tongue helps them locate the mouth of incapacitated prey so that they can ingest them head-first." said a skunk.
"Very good. It should only take about half an hour for Slybella to get Brian in her mouth and down her throat." Dr. Bentenson said.
"Maybe he'll get stuck." said a rabbit hopefully.
"I don't think so. Now, could someone name the fucntion of the esophagus?" Dr. Bentenson said.
"The primary function of your esophagus is to carry food and liquid from your mouth to your stomach. When you swallow, food and liquid first move from your mouth to your throat (pharynx). A small muscular flap called the epiglottis closes to prevent food and liquid from going down the “wrong pipe” — your windpipe (trachea). Another small flap called the uvula helps prevent liquid from passing upward into your nasal cavity. At the opening of your upper esophagus, there’s a ring-shaped muscle called the upper esophageal sphincter. Your upper esophageal sphincter senses when food or liquid is coming toward it. When it gets the signal, the sphincter relaxes or opens so that food can enter your esophagus. When there’s no food or liquid in sight, it stays closed. Once inside your esophagus, waves of muscular contractions (peristalsis) push the food downward. The food passes to the lower esophagus. At the opening of your lower esophagus, there’s another ring-shaped muscle called the lower esophageal sphincter. Like the upper esophageal sphincter, it senses when food and liquid are coming. It relaxes and lets the food pass through to your stomach. When no food or liquid is coming its way, it usually stays shut to prevent stomach acid and digestive juices from getting into your esophagus." said a mole.

"Correct. Also, it should be noted that snakes don't have a diaphragm. Can you tell us what’s the difference between the trachea and the esophagus?"
"Your trachea (windpipe) and your esophagus are both muscular tubes located within your neck. However, they have two very different functions. Your trachea is part of your respiratory system, and your esophagus is part of your digestive system. Your trachea transports air in and out of your lungs, whereas your esophagus transports food and liquid from your throat to your stomach." said a mole.

"Correct. Now, Brian, I believe it's time for you to go into the snake cage."
Shaking from head to foot, Brian climbed down a rope ladder into the cage. The snake, Slybella, was asleep. However, his arrival in the cage awakened her. She stuck out her tongue, scenting the air. She scented her prey and slowly moved toward the mouse. She was used to being given meat such as mutton and chicken and hadn't had live meat since she had been captured and taken to the school as a pet. She felt that this was her luck day.
Brian, however, was feeling very nervous as he saw the snake's slow approach. He knew it was all going to be unpleasant from here for the next entire week. Slybella reached him and he flinched as her wet and slimy tongue flickered across his face and she began to taste her prey with her tongue. Brian considered making a run for it, but noticed with alarm that the rope ladder had been removed.
"I removed this so that you wouldn't be tempted to run." Dr. Bentenson said in response to his look of horror. Now Brian was trapped and there was no turning back. There was no way he could fight off this snake so the only way forward now was done her throat, through her digestive tract, and out her cloaca with her wastes.

Slybella continued to lick him as her body began to slowly wrap around him, starting to squeeze him. He'd read that this is how python's deal with their prey, so he decided to pretend to go along and pretend to lose consciousness. It was hard to avoid flinching as the snake continued to lick him, but, somehow, he managed. After she had licked him over, she put him into her mouth and sucked on him. He didn't like this and squirmed. Slybella, however, knowing that she had subdued him, didn't care. He would digest in her stomach so it made no difference if he was still conscious and fighting. Brian gagged as her breath washed over him. It reeked. He hoped that his air fresheners were strong enough to mask it. Soon, after sucking on him, she began to move him toward the throat. His head passed under her uvula and soon his torso. Several minutes after that, she swallowed had his head in the back of her mouth and going into her throat. Some minutes later, she had fully in her mouth and then swallowed him with a loud and powerful GULLLLLLLLP!

"Now Brian is passing down her throat, moved by peristalsis. The trip is slow due to the length of her esophagus. In about fifteen minutes, he should pass through the area of her diaphragm. After this, he will continue until he goes through the lower esophageal sphincter and into the stomach." Dr. Bentenson said. Brian could him him talk, though it seemed further and further away, the further he descended. Luckily, he had a communication device so that he could talk to the teacher and the class. It even had video capability. Right now, though, there was nothing much to see inside the dark esophageal tunnel. It sure did take a long time for him to descend, but soon, he reached the sphincter and was deposited in the stomach.

Chapter 5: The Stomach

Brian was glad that the stomach was devoid of acid. The air in there was hardly breathable. He quickly changed into the anti-digestive suit that Dr. Bentenson had made and put on the breathing mask. At least now he could breathe better, and, hopefully, he wouldn't be digested. The stomach was large, over ten times his size. It was pink and muscular. He could hear the breathing of the snake from her nearby lungs and the beating of her nearby heart. He could also hear her leftovers from her stomach, which had drained some hours before he was swallowed, gurgling below him inside her intestines. He turned on the light of his phone and could see the cardiac sphincter above him at the top of the stomach, sealed shut. As he moved the beam to the floor, he could see the pyloric sphincter leading to the small intestine, also sealed shut. He was going to be inside the stomach for quite a while.

"Brian, please turn on your phone's camera so that we can see the inside of the stomach." came the voice of Dr. Bentenson. Brian quickly turned on the phone. "Good. Now, class, as you can see the stomach. At the top is the cardia. It mainly contains the cardiac sphincter. The next part is the fundus. It stores gas from digestion and also stores food if the stomach gets too full. The body of the stomach is the part that contracts and mixes food. It's the biggest part of the stomach. The antrum is at the bottom in the tunnel shaped part. It is where the stomach connects to the small intestine. The bottom of the stomach is the pylorus, which contains the pyloric sphincter.
"The stomach is the main part of the snake's digestive system, and, indeed, most digestive systems. In a snake, the food can remain in the stomach for four days."

"Looks like Brian is going to be there a long time!" laughed a possum.
"Yes, he is. But he should survive." said Dr. Bentenson.
"What if he doesn't?" asked another student.
"Let's hope that he doesn't die." said Dr. Bentenson.
"Doesn't Slybella's stomach have acid in it?" asked the possum.
"Yes, it normally does, but Slybella recently drained her stomach, so it'll be empty for a while. When it does fill, it will fill with hydrochloric acid, which is strong enough to digest bones."
"Maybe Brian will get digested into nothing and nobody will ever know what happened to him."
"I've made precautions to avoid that event from occurring."
"Damn it! You ruined the fun."
"I don't believe in having students be digested alive, even the most annoying ones."
The rest of the class period slowly went by, without anything eventful happening for Brian. He was getting hot and so drank some of the water that he'd brought with him. Thankfully, he'd frozen it before coming to school, so it was mostly still cool, despite now being inside the belly of a snake for about an hour. Slybella, meanwhile, slithered her way over to her milk dish, drank some, which doused Brian inside her stomach, and then slithered to a large rock, resting in the sun. She planned to just chill while she digested her meal. And besides, there was nothing really for her to do inside her cage. She was, so far, all alone. No boys to play with her.

The bell rang, signaling the end of the first class period. The students all filed out. Over the next several minutes, as the second period began, Dr. Bentenson told the class about the experiment he was doing that involved Brian. "Hey Brian, how's it like in there?" one of the students called out.
"Kind of smelly, though it's not that bad with these air fresheners and this breathing device."
"Is it cramped in there?" "Not really that bad. I think she could fit ten of me in here."
"Are you being digested?"
"No, there's no acid in here."
"Will you be digested?"
"I hope not. Dr. Bentenson said this suit should stop me from getting digested."
Brian felt Slybella move. She had awoken from her nap and noticed that meat had been placed in her cage. It was slabs of steak. She swallowed these, one at a time. They soon landed in the stomach beside Brian. Brian sighed. He was going to have to get used to this. Slybella soon drank more milk, splashing Brian in her stomach.
"Are you ok in there, Brian?" a female fox asked.
"Yes."
"Are you getting bored?"
"Yes. not much to do in here."
As the second hour of class came to an end, Brian felt the urge to urinate. He'd drank some soda in the stomach, due to it being hot and making him thirsty. He quickly switched off his communication device (which had been given to him by Dr. Bentenson as a backup for his phone, when it was being charged, which it was right now. It lasted twice as long as his phone.), unzipped his pants, pulled out his penis, and let loose a torrent of piss at the stomach wall. He watched as it trickled down the stomach call, coming to rest at the floor of the stomach along with the milk, making bubbles as it mixed with it. When he had finished peeing and put his penis back inside his pants, he turned back on the communication device. "Sorry, had to take a little pee break."
The rest of the day slowly went by, with little changing inside the stomach. Around noon, which he could only tell by his watch and his phone, he ate lunch. As he finished his lunch, something finally happened. He could hear gurgles around him and felt something splash against him. It wasn't milk, but something hotter. it was stomach acid. Thankfully, the suit seemed, so far, to be protecting him. "Looks like something finally is happening." Brian said into his communication device.
"What, specifically?" came Dr. Bentenson's reply.
"Acid is entering her stomach. Digestion is beginning, or will be for this meat she ingested, but hopefully not for me."
A short time later, as the class filed into the room, Dr. Bentenson again told the class what was going on, this time pointing out that the digestion had started. "The PH level will slowly drop as time goes on, eventually reaching 1.5. This is strong enough to digest even bones. However, with this suit I made for Brian, he shouldn't be digested. However, there will be some discomfort in the stomach. As the snake doesn't have teeth that chew, its stomach will slowly process the meal by squeezing it. While the suit should prevent suffocation, there will be times when the stomach will be quite cramped."
"Oh shit, I forgot about that part!" Brian groaned.
"The stomach won't even be the worst part of the digestive tract, I'm afraid." said Dr. Bentenson.
"At least I won't have to deal with that part for a while."
"Can anyone tell my why a snake's stomach take so long to digest its food?" Dr. Bentenson asked the class.
"Because they have a slow metabolism." a rabbit said.
"Correct, and why do they have a slow metabolism?"
"Because they are ectothermic, which means that they rely on their environment to regulate their body temperature. Since they don't have to expend as much energy to regulate their body temperature, that slows down their metabolism." said a gerbil.
"Correct. And what is another reason why a snake would digest food more slowly than other animas?"
"Because they eat food whole. Their stomach can even digest bones. So that also takes more time." said the rabbit again.
"Correct. Thankfully, that suit I made for Brian should prevent his bones, or any other part of him, from being digested."
"Let's hope so." Brian said.
"Can anyone tell me the stages of digestion?" Dr. Bentenson asked.
"Ingestion, propulsion, mechanical digestion, chemical digestion, absorption, and defecation." a fox said.
"Correct. Ingestion involves the mouth while propulsion involves the esophagus, where food is moved by peristalsis to the stomach. Can you tell me the difference between mechanical and chemical digestion?"
"Mechanical digestion does not change the chemical nature of the food. It just makes it smaller and compacts it. It involves chewing, churning in the stomach, and segmentation in the small intestine. Chemical digestion, on the other hand, does change the chemical nature. It starts with secretions in the mouth and then acid in the stomach. By breaking the food down in this way, it enables the villi in the small intestine to absorb the nutrients into the bloodstream."
"Correct."
As Dr. Bentenson and the class talked, Brian looked at the meat that Slybella had swallowed. It was beginning to sizzle as the acid hit it. It was first breaking into chunks and then, as time went on, starting to change chemically. Thankfully, the suit was keeping him from digestion. However, he did notice that the air was becoming stifling, due to the digestive process generating heat. He wanted to strip off the suit, but he knew he'd be toast without it. This was going to be a long four days!

"Can anyone tell me what the contents of the gasses in the stomach are?" Dr. Bentenson asked.
"Smelly stuff!" Brian said. The class laughed.
"Could anyone be more specific?"
"15 to 16 percent oxygen, 5 to 9 percent carbon dioxide, and the rest nitrogen. The air breathed in is about 21 percent oxygen, and some of it is absorbed by the blood capillaries in the stomach. The carbon dioxide is made by the reduction of the food by the stomach's gastric juices. The nitrogen is not absorbed as a gas and is just moved on." said a pig.
"Very good."
The rest of the day slowly went by. Brian watched as the food that Slybella had eaten was slowly broken down into watery chunks. The mess, as he learned from Dr. Bentenson's talking, was called chyme. During the last class period of the day, Brian was interrupted from his daydreams by a sudden shaking and loud noise in the stomach. Slybella had burped. Thankfully, the suit allowed him to continue breathing, despite the decrease in the air supply. "Does anyone know what is usually expelled during burping?" Dr. Bentenson asked.
"Yes, nitrogen and oxygen." Brian replied.
"Correct."
At long last, the school day was over. Brian had been taking notes the whole time, for he would get an exam on all discussed on a snake's digestive system, instead of the final. As he was experiencing it personally, he thought that that would help with remembering the material enough to ace it. Plus, he literally had all week to study the material. After class was over, he could take it more easily. He no longer had to take notes, unless something important happened. He would still do videos often for the sake of the research (Dr. Bentenson was going for a Noble Prize for his work), but could now take many breaks, including sleeping. He doubted he could get much sleep in here, but at least he could try. "I'll see you tomorrow, well, you know what I mean." Dr. Bentenson said as he left and locked the class door forty minutes after the school day had ended and it was time for him to go home for the night.
"Bye."
The hours slowly went by. Around evening, Brian, who had been studying his notes, was hit by milk that Slybella drank. He groaned. This was hard to get used to. So was riding in the large soup of what had once been Slybella's breakfast. There were some chunks of meat still discernable, but a lot of it was now more chyme than a solid substance. He could fell Slybella slithering across her cage, moving to he knew not where. He was now used to her moving and was able to keep his balance, but he recalled a time earlier that day when he'd been taking a leak, only to be knocked over and land face down in his own piss.

It must be boring to be a snake in a cage all day, he thought, just about as boring as being trapped in a snake's stomach all day. He felt the snake stop and move around and around. She was curling up on a rock to sleep for the night. He could hear the steady rhythm of her breathing as she dozed. He could also hear her heart rate decrease as she went to sleep.

Brian felt nature's call. And, since he hadn't had a bowel movement since Saturday, he felt that now was as good a time as any to go Number Two as well. He turned off the camera, pulled down his pants and underwear and bent into a squat. Urine splashed down to the stomach floor as he peed, sizzling as it hit the acid. Soon, a log of shit fell out of his open anus and landed in the acid below as he defecated. He finished emptying out his wastes and then wiped himself, before quickly pulling back on his pants and underwear. He turned the camera on, recording as his excreted waste began to bubble and foam as the acid softened it. It was now more the composition of melted fudge than logs of feces. Around 1 AM, Brian nodded off, dozing as he rested against the stomach wall. He was awoken around dawn, as the stomach began to shift. Thus far, the digestive process had just consisted of acid pouring in and trying to break down the stomach contents, Now, however, peristalsis had set in.

"Damn wake up call this is!" he moaned. By the time class had started, the stomach was making regular contractions as it tried to process him. "How are things going in there?" Dr. Bentenson asked.
"Very cramped. The stomach is starting to contract."
"This process is called peristalsis. Can anyone here tell me what that is?"
"It is an involuntary wavelike contraction of muscles in the throat, stomach, and intestines. In the esophagus and intestines, it moves food along to the exit, in this case the cloaca. In the stomach, it helps process food and break it down into chyme, which can be absorbed by the villi in the small intestine." said a fox.
"Very good."
"Unfortunately, you said that this process will take a few days before I leave the stomach." Brian sighed.
"I did. A snake's slow metabolism requires that it take this long. I'm afraid you haven't even seen the worst of the contractions yet. Those won't be till the last day in the stomach."
"Just great!"
Time slowly went by. The contractions of the stomach slowly increased. Slybella ate more meat, which was slowly broken down. "Can anyone tell me how bacteria help break down food in the stomach?" Dr. Bentenson said.
"There are 100 trillion bacteria inside the gut. They help break down complex sugars known as polysaccharides. The bacteria break these down into glucose molecules, which are more easily absorbed by the intestines. They produce sugar-breaking enzymes such as such as polysaccharide lyase and carbohydrate esterase. One side effect of the bacterial activity is that they produce gas." said a squirrel.
"So, that's where farts come from!" said a hen. The class laughed.
"More like stomach gasses. Flatulence is different from stomach gasses. We'll discuss 'farts' when we get to the large intestine. Anyway, bacteria also help to produce vitamins that we cannot produce ourselves, especially the B group. " added Dr. Bentenson.
As the day went by, the growling of the stomach grew louder as the digestive process intensified. The smell of the gas also grew worse. While the mask from his suit kept out most of it, it didn't kept out all the smell. Also, the suit wasn't proving to be 100% effective against the stomach acid either. By the end of the second school day, he was starting to have an itch, as some of the acid bypassed the suit. Thankfully, this was, so far, the worst of the damage. He now was having to shield his penis whenever he peed, to keep it safe from stomach acid. His urine quickly sizzled as it hit the acid below. He was peeing quite regularly now, as the hot interior of the stomach made him very thirsty. He was very glad that he'd had the foresight to stash lots of fluids. As night fell, he knew that, with the contractions of the stomach, this night he'd be lucky if he got any sleep at all. He managed an hour and a half, due to exhaustion, but that was it before again being woken up at dawn as Slybella stirred.

"How are things in there?" Dr. Benenson asked.
"Cramped. And the acid level is slowly rising."
"Yes, well, it shouldn't hurt you thanks to that suit."
"It has gotten to me a little bit, but not much, thankfully."
"I guess I'll have to work on the kinks in it when this is all over. At least it's mostly doing it's job."
"Yes, this is some suit."
Dr. Bentenson turned to his class. "Can anyone here tell me what stomach acid is and where it comes from?"
"It comes from the stomach, duh! That's why they call it stomach acid." snorted a smart-aleck ferret. The class laughed.
"Stomach acid, or gastric acid, is secreted by the lining of the stomach. It is made of hydrochloric acid, potassium chloride, and sodium chloride. The stomach walls secrete mucus, which protect the stomach from the stomach acid." said a rat.
"Correct."
The rest of the day went on, and so did the next. The acid level continued to rise, eventually filling the stomach. The contractions were constant and the food had been so reduced that it was now impossible to tell what it had once been. The acid had burned off some of his fur, but it would easily grow back before he was excreted. As the fourth day inside Slybella dawned, and as class began, something finally happened. The stomach began to drain. Slowly, he approached the bottom. "Looks like the stomach is draining."
"Good, your first stage of the trip is done now." said Dr. Bentenson. Brian reached the bottom, and was slowly squeezed through the sphincter. Finally, with a large push, he was squeezed fully out of the stomach and in to the small intestine.