Urine Formation Process and Its Affecting Factors

Urine Formation Process and Its Affecting Factors
The process of forming urine includes 3 components, among others: filtration, reabsorption, and augmentation. Urine is a residual liquid metabolism produced by the kidney which is then released through the urine. Urine consists of water and a variety of materials dissolved in it. These dissolved materials are the remnants of body metabolism such as dissolved salts, urea, and other organic matter.

The main organ of the urinary system is a pair of kidneys. The organ is brown red and shaped like a kidney bean. The location of the kidney organ is located in the waist area, which is precisely in the back of the abdomen and protected the ribs. The kidneys filter out blood that already contains the metabolic waste substances from the body's cells.

The formation of urine through a series of long processes that continue to occur every day and repeatedly. All the blood in the body passes through the kidneys many times a day. Blood enters the kidney through the renal artery. Then the blood leaves the kidneys through the kidney vein and the blood will undergo the process of formation of urine. Kidney consists of 2 layers. The outer layer is called the cortex and the inner layer is called the medulla.

A kidney is composed of about 1 million nephrons. Nephrons are the smallest unit of filter found in the kidneys. 1 nephron is composed of the glomerulus, winding channel, Bowman Symphony, kidney collecting channel, and Ansa Henle. Sugar, water, salt, and waste substances that come from the blood will go into the nephron. At the time of entry into the nephron, high blood pressure. Blood can quickly flow into the capillaries of the nephron. These capillary groups are called glomeruli. For more details, the following process of urine formation:

Urine Formation Process

1. Filtering (filtration) 
The blood filtration or filtration process takes place in the glomerular capillaries, the curved blood capillaries found in Bowman's capsule. In the glomerulus, there are endothelial cells that can facilitate blood filtering. Blood-derived from the glomerulus then passes the epithelial cells of the Bowman capsule which is useful as a filter that can be called a podocyte cell. Podocyte cells can be penetrated by water as well as various small molecular, but cannot be penetrated by large molecules such as blood cells and blood plasma proteins.

In addition to the screening process, the glomerulus occurs the binding process of blood cells, blood clots, and some plasma proteins in order not to come out. The filtrate results in the form of glomerular filtrate or primary urine whose content is still similar to blood but does not contain protein.

Infiltration there is no selection of small molecules, so there are several molecules that enter the nephron channel. Therefore, in the filtrate can be found in the presence of glucose, vitamins, salts, nitrogen metabolism in the form of urea, and various other small molecules that reflect the presence of such substance concentrations in the blood.

2. Reabsorption
Primary urine is the result of a further screening process which then flows into the proximal vessels. In the proximal vessels the process of re-absorption of various materials that are still useful, among others: amino acid, glucose, and most of the inorganic ions. The water present in the glomerular filtrate undergoes absorption by osmosis process.

The process of water absorption also occurs in the distal vessels, the loop of Henle, as well as the collecting vessels (the falling vessels). Then, the ingredients that have been reabsorbed will be returned to the blood through the capillary vessels that surround the vessels. The absorption process of various materials that are still needed also occurs in the loop of Henle especially the absorption of sodium chloride ions.

In the process of reabsorption, will be produced secondary urine content of constituent substances are very different from primary urine. In the secondary urine, there is no substance that is still needed, and the content of urea levels increased compared with the urea content in the primary urine.

3. Collection (Augmentation)
In the augmentation process, the primary urine or the tubular filtrate of the proximal contract tubule then leads to the distal contrast tubule. Urine is then supplemented with various substances that are no longer needed by the blood capillary vessels. In the augmentation process, the urine is actually formed, the urine will go to the collecting tubules that eventually lead to the kidney cavity.

The kidney cavity is a urine reservoir that then flows into the ureter. While the ureter is useful for removing urine from the kidneys to the bladder.

From the kidney cavity, then the urine flows into the ureter toward the bladder. By the time the bladder is full, the walls of the bladder will be depressed. The pressure is what makes us feel like urinating or urinating. Urine will come out through a sewer called the urethra.

Human Urine Formation Process Scheme

From the process of formation of urine that has been described above, we can make the scheme as follows:

Glomerulus, filtration, produces primary urine -> proximal contortus tubules, absorption occurs (reabsorption) resulting in secondary urine -> distal contrast tubules, a collection process (augmentation) produces the actual urine -> collective tubules -> renal cavity -> ureter -> bladder -> urethra -> urine out of the body.

The normal urine composition comprises 96% water as well as 4% solids of which 2% urea and 2% of other metabolic yields. Other metabolic outcomes include bile dye which serves to give the yellow color to the urine, a variety of mineral salts such as sodium and potassium chloride, as well as a variety of substances that are excessive in the blood, such as vitamin C and B vitamins.

The volume of urine in humans is only about 1% of the glomerular filtrate, which means that 99% of the glomerular filtrate will then be reabsorbed. Every day, the amount of water reabsorbed about 178 liters, 150 grams of glucose, and 1,200 grams of salt.

Residual substances:
1) uric acid, urea, and ammonia which are the remains of protein disassembly.
2) Mineral salts, especially the salt of the kitchen.
3) Gallstones, which can cause the urine to become yellowish.
4) Excessive substances in the blood, such as drugs, hormones, and vitamins.

Doctors at the time of diagnosing the disease can by knowing the content of substances that exist in the urine of patients by passing a urine test. A person whose urine still contains sugar content indicates that the person has diabetes, while in the urine that still contains protein content indicates the presence of damage to the kidneys.

Factors Affecting Urine Production

The daily urine is always different, this is due to the influence of the following factors:

1. Antidiuretic hormone (ADH)
Antidiuretic hormone (ADH) has used to facilitate water absorption in the distal tubule and collecting vessels. If the water concentration decreases in the blood (the blood becomes thicker), then the hormone ADH will be secreted and channeled to the kidneys with blood. This allows the permeability of the collecting vessel wall and the distal vessels to water to increase so that the incoming water can be reabsorbed.

As a result, the urine formed becomes less. On the contrary, if the concentration of water in the blood is high (blood fluids become more dilute), then the secretion of ADH hormone will decrease, which makes the absorption of water in the collecting vessels and distal vessels become reduced and the urine formed will be dilute and many.

2. Amount of water to drink
If the amount of water drunk by a person is large, the water concentration increases and the blood protein concentration decreases. Therefore the colloid pressure becomes decreased so the filtration pressure will be less effective. As a result, the water absorbed becomes reduced. The production of urine produced will increase.

3. Insulin hormone concentration
If the concentration of insulin hormone is low (as in diabetics), so the blood sugar level is high and is removed by distal vessels. The presence of these sugars can interfere with the process of water absorption in the distal vessels. As a result, people with diabetes mellitus will often urinate.

Benefits of Urine Disposal

Food and beverages consumed than used the body as energy and to repair damaged cells. Substances beneficial to the body will be absorbed, while unnecessary substances will then be carried by the blood to the kidneys to be filtered. Thus, urine is removed in order to dispose of the remnants of the body (such as urea) and also the toxins present in the body. Urination is a method of removal of various water-soluble chemicals from the body.

A healthy kidney (normal) is a kidney that gets enough drinking water and can remove almost all substances that are not needed by the body. If you consume too little water, the urine will become concentrated. It can lead to inflammation of the bladder and kidneys.

That is the process of forming urine. At a time when the body sweats a lot and usually because of illness, our kidneys will lack water. This makes urine dark yellow. When we drink a lot of water, the blood will contain more water so the kidneys will produce more urine that is thin and yellow.