What Do Your Kidneys Actually Do?

Your kidneys are complex organs that are responsible for eliminating waste from your body through the urine. People usually have two kidneys that are located on the back of the abdomen, next to the spine and under the ribs.

Your kidneys are shaped like a bean. They are important organs as life is not possible if they do not function properly. However, thanks to technological advances, there are techniques such as dialysis or transplants that allow doctors to replace them.

In addition to urine production, the kidneys participate in many other processes, such as regulating blood pressure. Therefore, in this article we will explain what the kidneys do, their anatomy and their most important characteristics.

The anatomy of your kidneys

The kidneys, as we mentioned, are bean-shaped, with one side concave and the other convex. The renal artery enters the concave part, which carries the blood with the waste products from the body that goes to the kidneys. The renal vein and ureter are also based on that part.

The kidneys have two main parts: the cortex and the medulla. The cortex is the outermost part (the bark) and the one that gets the most blood flow. It is mainly responsible for filtration and reabsorption. In addition, it contains almost all the glomerulus, which we will explain later.

The medulla consists of a number of structures that are responsible for directing the urine that the kidneys produce to the ureter. The ureter is a tube that goes down to the bladder, which stores the urine it will later eliminate.

The functional units of the kidneys are the nephrons. The nephrons are the place where blood filtration takes place and urine is produced. There are about 800,000 nephrons in each kidney.

Their structure is very complex, but the basic idea is that they consist of a number of cellular structures and membranes that allow blood to pass and filter. In addition, they are responsible for excreting certain substances and resuming others, such as potassium.

What do your kidneys do?

We already mentioned that the main function of the kidney is to eliminate substances through the urine, but this is not the only function. This organ also plays a very important role in the secretion of certain hormones and substances.

First and foremost, we must emphasize that the kidneys allow vitamin D to be transformed into its active form. This vitamin is important for the metabolism of calcium. In addition, the kidneys produce erythropoietin, which is responsible for stimulating the synthesis of red blood cells in your body.

On the other hand, the kidneys are essential for certain processes that allow homeostasis in your body. In other words, they help your body maintain an inner balance even if the conditions in your environment change.

For example, they regulate both blood pressure and the pH level in your blood. They also control the plasma volume, as they change the urine concentration and can prevent water loss in situations of dehydration.

How do they filter the blood?

Blood reaches the nephrons through the renal artery, where this artery branches into smaller arteries that form the glomerulus. The glomerulus allows small molecules, liquids and toxins to pass into the tubules. In this way, they retain the largest elements, such as cells.

In addition, the glomerulus consists of a series of tubes where the body reabsorbs much of the filtered water or certain substances that it needs. For example, it can absorb sodium or potassium molecules.

Conclusion

It is important to remember  that your kidneys are complex organs that, in addition to producing urine, are responsible for many other functions. These include the synthesis of erythropoietin and the control of blood pressure.