Nephron Function in Kidney, Definition and Structure – After discussing the cortex, it would be lacking if we did not discuss the structure and function of the nephrons in the kidneys. For that, let's take a good look at this article.

The kidney has three structures consisting of the cortex, medulla, and renal pelvis. Where the smallest functional components of the kidney are known as nephrons.

Definition of NephronDefinition of Nephron

Basic structural and functional components kidney are nephrons. Where both are microscopic organs consisting of renal tubules and renal corpuscles.

Nephron is a word that comes from the Greek, namely nephros which means kidney. And each human kidney contains millions of nephrons.

Nephron Features

A complex epithelial tube with closed ends and open ends forms the nephron. The kidney is made up of several nephrons, which cluster together to make the collecting ducts, the papillary ducts.

The kidneys consist of varying numbers of nephrons which can be increased by an order of magnitude in small mammals compared to the simplest vertebrates, which have hundreds of nephrons.

More than one million nephrons can be found in humans and other large mammals.

Nephron Function

Nephron Function
Function of nephrons in the kidney the main thing is to remove all waste materials from the blood, including solid wastes and excess water. It also helps with the reabsorption, secretion, and excretion of many substances.

Small molecules are transported into the glomerular capsule and travel through a network of tortuous tubules as blood is pushed through the glomerulus at high pressure.

Glucose, water, and other beneficial chemicals known as ultrafiltrate are not absorbed by the cells found in each tube.

More water is removed from the ultrafiltrate before leaving the nephron as a result of the ultrafiltrate molecules becoming more hypertonic as they descend down the tubule.

The renal vein, which is free of toxins and other foreign elements, is where the blood that surrounds the nephrons returns to the body.

Urine, the resulting ultrafiltrate, passes through the collecting ducts and into the bladder, where it is stored and excreted through the urethra.

Nephron Parts

The nephrons of mammals, which range from 35 to 55 mm in length, are long, tube-like structures.

The tube is closed, folded, and inflated at one end to form Bowman's capsule, also known as the renal corpuscle capsule, which houses the glomerulus, a tiny blood capillary structure.

The renal corpuscle is formed by this capsule and the glomerulus is joined. The nephron structure is divided into two main parts, namely:

1. Kidney tubules

Based on their function, the renal tubules, which are long, wavy structures that emanate from the glomerulus, can be categorized into three groups.

Because of its proximity to the glomerulus, the first portion is known as the proximal convoluted tubule (PCT), and remains in the renal cortex.

The second component, which forms an arch with the foot rising and falling, and running through the renal medulla, is known as the loop of Henle or the nephritic arch.

The distal convoluted tubule (DCT), the third component of the renal tubule, is also confined to the renal cortex.

Bowman's capsule, a cup-like structure, encloses the glomerular capillaries. Highly coiled tubules known as PCTs form when these structures are stretched.

The loop of Henle is still formed by the PCT as it ascends into the DCT, which eventually opens into the collecting duct.

Reabsorption is a major function of the tubules, and can occur by either active or passive transport.

In addition, tubular secretion contributes to urine production without disturbing the electrolyte balance of the body. Here is the explanation:

Proximal Convoluted Tubule (PCT)

The glomerulus filters the blood carried by the renal arteries before sending it to the PCT. The PCT of the nephron is the site of greatest reabsorption.

Reabsorption of important chemicals such as glucose, proteins, amino acids, most electrolytes, and water occurs in the PCT, which is part of the renal tubules.

The cuboidal epithelium layer directly on the inside increases the surface area for absorption. Reabsorption uses energy, indicating that the process is taking place.

In the filtrate, PCT preferentially removes ions including hydrogen, ammonia, and potassium while absorbing HCO 3 -. Therefore, the electrolyte and acid-base balance of body fluids is maintained by PCT.

Henle's circle

Henle loops or loops of Henle have limbs that go up and down. The ascending and descending limbs of the loop have different permeabilities even though they are components of the same structure.

The ascending limb is impermeable to electrolytes but is permeable to water, whereas the descending limb has the opposite property.

The filtrate becomes dilute as it approaches the ascending limb because electrolytes are reabsorbed in the ascending loop of Henle. But only this part can be reabsorbed.

Distal Convoluted Tubule (DCT)

The DCT, which is the final component of the nephron, joins the collecting ducts that surround the medullary pyramids and releases their contents into them.

The renal medullary papillae are where the collecting ducts join after collecting the contents of several nephrons.

Similar to PCT, DCT reabsorbs HCO3 from the filtrate while expelling ions such as hydrogen, potassium, and NH3 into the filtrate.

In DCT, sodium ions and water are conditionally reabsorbed. As a result, it keeps the blood cell pH and sodium-potassium level stable.

Collector Duct

To maintain blood electrolyte balance, H+ and K+ ions are excreted through long straight tubes called collecting ducts.

In addition, most of the water is reabsorbed here, which leads to concentrated urine.

2. Kidney Cells

Kidney CellThe glomerulus and Bowman's capsule surround the renal corpuscle. The afferent arterioles give rise to the glomerulus, which empties into the efferent arterioles.

The smaller diameter of the efferent arterioles contributes to the ability of the glomerulus to maintain high blood pressure.

Bowman's capsule has three layers, including:

  1. It consists of epithelial cells with holes up to 12 nm in diameter in the outer parietal layer.
  2. The middle basement membrane, is the layer that can let air in but nothing else.
  3. Podocytes, which are large nucleated cells in the inner visceral layer, have podocells, which resemble finger-like extensions.

Tips for Having Healthy Kidneys

Kidneys are important organs that can affect many other parts of the body, including the heart.

Here are some ways you can keep your kidneys healthy and working efficiently:

Avoid Extra Salt

Consuming too much salty food can certainly disrupt the balance of minerals in the blood, so it can inhibit the kidneys from working properly.

For that you can replace processed foods with whole foods such as fruit, lean meat, healthy vegetables, and nuts.


SportOne of the risk factors for chronic kidney disease is high blood pressure, so you are advised to exercise regularly, even if it's only 20 minutes a day, because this can help you lower your blood pressure.

Stay Hydrated

One of the important functions of the kidneys is to remove toxins, so you are advised to drink lots of water to help the kidneys carry out their important functions.

Take Drugs with Care

If you take over-the-counter drugs regularly, such as non-steroidal anti-inflammatory drugs, it will certainly cause kidney damage over time.

Even if you feel better when you take the drug, you should still ask your doctor about this.

Know the Risk Factors

Apart from that there are several things that can increase your risk, so it is recommended that you do kidney function tests regularly, if:

  1. suffer diabetes
  2. Have high blood pressure
  3. Obesity
  4. Have a family history of kidney disease.


Here we have summarized some frequently asked questions about the function of nephrons in the kidneys:

What Is meant by a Kidney Nephron?

Nfron is one of the important parts in the kidney, which has the task of filtering the blood which then takes its nutrients and makes waste products from the results of metabolism.

What's Inside the Nephron?

These nephrons are composed of renal bodies or maphigial bodies which are located in the middle of the kidney.

Where malpighian bodies consist of channels or tubules that contain glomeruli in Bowman's capsule or capillary rolls.


That's a little information about the meaning and function of nephrons in the kidney that you need to know.

And from this article we can conclude that the kidneys are the main organ in the human excretory system, although excretion in humans also occurs through the skin, liver, lungs,

The kidney is an organ that has a bean-like shape, weighing 150 to 170 grams, which is located just below the rib cage.

Thus the article this time and don't forget to keep visiting the Infokekinian website. Because we also have a lot of other information and recommendations which of course will be useful and help current friends.