The kidneys are an underrated pair of organs. We’re not sure why. Maybe it’s because if you lose them, you can still continue to live with some help from dialysis. This is in opposition to losing a heart, brain, or liver. But despite the way some people brush off kidneys as less than significant, life sort of sucks without them. The kidneys’ job isn’t “making urine”; that’s just a fun waste product! Nope. Kidneys regulate what stays or leaves the blood; they also control blood pressure and play a role in building strong bones.
Let’s Get To It
Hey, this newsletter is supposed to be about nephrons! Yes, you’re right. HOW the kidneys do their job is thanks to the nephrons. In short, nephrons are the functional units inside of kidneys. Each unit is essentially a folded-up tube, but just like your intestines, a folded tube can have multiple functions. So hold on, and let’s ride through the nephrons like a sodium ion.
We Keep Important Things
We’ll first start at the glomerulus. This is a tight ball of blood vessels that transports you into the kidneys, then unceremoniously dumps you into Bowman’s capsule. Welcome to the nephron! You and your other friends in the blood all get dropped off here, and the important ones are quickly reabsorbed back. In a healthy adult, things like amino acids, glucose, and other critical organic molecules are precious commodities, so they’re returned to the body.
In or Out?
You, on the other hand, are a sodium ion, so you get to keep traveling down the tube. In the descending loop of Henle, water molecules wave goodbye and are absorbed back into a blood vessel. In the ascending loop of Henle, all your ion friends get dumped back into the blood too. Somehow, you manage to stay in the nephron.
Staying or Going?
At the end of this convoluted tube is your last test. Depending on whether the human is dehydrated and needs to conserve water, or if they drank too much water, you’re either brought back into the bloodstream (since water molecules tend to like to follow you) or you head to the bladder. Here you can rest before leaving the body, and someone eventually flushes you down the toilet. Of course, you might get lucky and end up in the cup of one of those urine drinkers, and then you can start the journey through the body again!
You Need A Nephron Map
Well, we hope you enjoyed the ride through the nephrons. If you’re in need of a map, we actually sell a lovely 3D printed version of the nephron so you can find your way every time you wear it! This nephron necklace makes the perfect gift for other lost sodium ions, nephrologists, athletes worried about hydration, or starry-eyed pre-med students.
written by Science with Evie