What if urine was reprocessed by large intestines?
What if urine was reprocessed by large intestines?
I have wondered many times how a human would fare if the kidneys dumped urine into the start of the large intestines somewhere about the appendix instead of into a bladder to be sprayed out. I'm assuming water would be reabsorbed and slower to process out, primarily through sweat and evaporation from the lungs, and maybe diarrhea, though it may be that other waste products, such as salts or ureas may be absorbed into the large intestines instead of being ejected, though I have no idea if it would, or if it would be ejected as intended. Do we have any biologists here that could give insight on if combining both waste paths into one would be advisable?
Am doctor, you are essentially asking about a fistula (abnormal communication) that would allow urine and bowel to mix. This would allow for communication of gut bacteria to then invade the urinary system which would then easily cause a kidney infection which would then seed the blood resulting in bacteremia. Bacteremia is bad, like you die from infection unless you are on IV antibiotics and get the source under control bad. As an example, colovesicular fistula is a communication between the colon and bladder which often results in bad infections and needs to be surgically repaired. Hope this helps.
46Hey, doc. Every time I hit my elbow with a hammer, it hurts real bad. Got any advice?
29Keep at it. The feeling should subside eventually.
45
Ok but why cant I have a secondary urethra grafted in that runs in my leg down to a nice discreet exit on my ankle so I can take a sneaky wee when Im out and about.
19No he's asking what if humans had cloacas
7I can totally see that, though what if the body was able to adapt to the new configuration and keep the gut bacteria in its place, but the urine still flowed into the bowels for reprocessing? What else would the large intestines pick up aside from water and maybe salt?
1
Consider, for a second, what would happen if and when the pressure in the colon exceeded the pressure in the bladder, and a urethra connected the two: fluid in the colon would backfeed into the urinary tract. The kidneys would ultimately be exposed to intestinal flora.
The prevalence of UTIs even with the "air gap" of separate waste streams tells me that this would be an extraordinarily bad idea, at least with our current biology.
If we had evolved in a more arid environment, there might be some advantage, but if we had, we would have a significantly different system to maintain homeostasis: it would have to be significantly more resilient to bacterial contamination than our current system.
26Can confirm, there is a condition that removes the air gap causing a pretty much continuous UTI. (Colovesical fistula: https://www.medicalnewstoday.com/articles/colovesical-fistula#treatment-and-management)
15
I have Crohn's disease and therefore already pee out of my a$$ on a regular basis.
0/10 would not recommend.
(obv. not exactly what OP is asking but i imagine it feels the same)
20Ditto. I had my large intestine removed and now adding even more liquid would not be pleasant.
7
Then you'll basically have a cloaca, and perhaps you'll ended up like bird and reptile which can't seem to hold their shit and also have watery shit. One of the great things about mammals is they're able to hold their (relatively) dry shit until they found a safe place to dump it.
19That might be a trainability issue rather than a physical capability issue, the more intelligent parrot species are able to be trained to defecate either on command or in specific spots.
2
Well, then urine trouble because that would be like having liquid poo all the time. Gross.
12The kidneys already recover water and salt. Google the loop of Henley.
What we pee is what our body considers in excess. We intake a lot of our water from food, so we need a way to expel that. Peeing is much nicer than bloating and constant Diarra.
11True, though as is, we still need to take in water due to a shortfall in what we do take in. That said, I'm also wondering if my proposal would also result in other waste products being recirculated and building up in the system, causing their own complications.
0You are asking for kidney stones. There's a chemical reason you want plenty of water to dilute your waste, that is avoid precipitation
Edit https://en.m.wikipedia.org/wiki/Precipitation_(chemistry)
7One waste product building up would be water, in that case
1
Not a biologist, just a normal dude. Isn't one function of urine to flush out toxins? With them staying in the intestines could it poison the human?
4That's actually part of my question. The bowels also dump toxins overboard as well, but will they be enough to do the job?
2I think you need to perhaps watch some videos explaining the anatomy/physiology of the gastrointestinal tract and urinary tract.
The kind of questions you're asking can be easily answered with an understanding of the systems I've stated above.
2
You're looking for a Cloaka
2A cloaca still has facilities for urine to be dumped overboard, doesn't it? My proposal is to recirculate it before dumping it overboard dry.
1And what would you do with the water you've taken out in the drying process? Have seperate organs to seperate it (kidneys, colon) and a seperate set of organs to dump it out (pee)? That's returning to the way we humans handle it. Or you need to stop flushing things with the water and stop eating food that contains it. Or your organism just accumulates water and explodes like a water balloon if it has no way to get out. It has to go somewhere if you ingest it.
1
The other solution would be to evolve a bladder capable of reabsorbing water.
1That is also something that I have wondered about, but that probably isn't a thing because of salt buildup.
1
The beargryllneys?
1What if my mother had wheels?
0I think that's called a bicycle.
4