Hello, again internet world!
To start off my revisions for Biology & Human Biology and Organic Chemistry, I will start with revising the information that has been stored in my brain most recently, which would be the Urinary System.
I never knew much about the urinary system or how the kidney’s make urine so the past 2 weeks of lectures on the urinary system were all very new to me. And if I’m being honest here, I am quite unsure of what the kidneys are called in Korean (I’m Korean-American so I should know this🙈). But oh well, I’ll learn it someday!
So, time to get crackin’ with my hair tied up, some Jazz playing in the background, windows open for fresh air, got my big glass water bottle out for hydration, and most importantly I have just got back from the toilet having done a wee! The result of my kidney’s properly functioning!😁 (this is the type appreciation you gain when you learn about the human body lol)
Our urinary system has it’s main organ which are the Kidneys; kind of like the principle dancer in a ballet so to say. The main attraction who does the most dancing and gets most of the attention/credit. The rest of the organs are the Ureters, Bladder, and Urethra; in this case the corpse de ballet in a ballet. They don’t have as much of a big role, they’re not as appreciated as the principle dancer, but the ballet certainly would not be complete or functional without the corpse de ballet. And no, the ureter and the urethra are not the same (I didn’t know that either).
So what do these organs do? Since the kidneys have the biggest role in the urinary system, let’s start with the kidneys.
The kidneys are two fist-sized, bean-shaped organs that are near where your lowest ribs are. They also always have a friend, the adrenal glands (will explain this in the future) sitting on top of them. The kidneys have 3 layers of supportive tissue to protect, encase, and anchor them to their surrounding area. These layers are called the fibrous capsule, perineal fat capsule, and the renal fascia.
This diagram here is an illustration of the kidney anatomy, also called renal anatomy. You will start to notice that anything “renal” is related to the kidneys. There are about 8 lobes in each kidney, each compromised of the cortex, medulla, renal columns, calyces, and pelvis (no, not the pelvic bone).
As you can see, the cortex is in the outer region of the kidney and it is where ultrafiltration (filtration of blood to urine) occurs. The medulla is located more inwards than the cortex, and it makes up the renal pyramids as you can see in the diagram. The renal pyramids are made up of tons of nephrons (we’ll get to this) which is responsible for the main filtering job of our blood. Calyces are the tubes that collect freshly made urine from the pyramids and the funnel-shaped renal pelvis then sends the urine to the ureter which then eventually collects in our bladder.
Going back to the main organs in the urinary system, the ureters are the tubes connecting the kidneys to the bladder. But fun fact, urine doesn’t just go down through the ureter to the bladder because of gravity, it moves down through a movement called peristalsis which is movement caused from smooth muscles surrounding the ureter that kind of massages the urine down to the bladder in a wave-like contracting movement. It also has valve like folds to prevent urine from backflowing up to the kidneys.
Once the urine goes down the ureter through peristaltic movement, it is collected in the bladder until it is excreted from the body through the urethra. The urethra once again pushes urine out of the body through peristaltic movement.
So this is the very basics of the urinary system. Since the urinary system is very complicated with so much information, I will continue with how filtration happens in the next post.
If you are revising for an exam like me or have just read this from curiosity, either way, I hope this post wasn’t boring and that it was easy to understand my use of words.
Till next time!