Question

Как работают почки ? где первичная моча и где вторичная моча ?

Answer 1

How do kidneys work?

The kidneys are vital organs in the human body that play a crucial role in maintaining overall health. They are responsible for filtering waste products and excess fluid from the blood, regulating electrolyte levels, and producing hormones that help control blood pressure and stimulate red blood cell production.

The process of how the kidneys work can be summarized in the following steps:

1. Filtration: Blood enters the kidneys through the renal arteries, which branch off from the aorta. Inside the kidneys, there are millions of tiny filtering units called nephrons. Each nephron consists of a glomerulus and a tubule. The glomerulus acts as a filter, allowing small molecules like water, electrolytes, and waste products to pass through while retaining larger molecules like proteins and blood cells.

2. Reabsorption: After filtration, the filtered fluid, known as the primary urine or filtrate, enters the tubules of the nephrons. As the primary urine flows through the tubules, essential substances like glucose, amino acids, and electrolytes are reabsorbed back into the bloodstream. This process ensures that the body retains necessary substances while eliminating waste products.

3. Secretion: In addition to reabsorption, the tubules also actively secrete certain substances into the primary urine. This includes substances like hydrogen ions, potassium ions, and certain drugs. Secretion helps maintain the body's acid-base balance and eliminates any excess or harmful substances.

4. Concentration: As the primary urine continues to flow through the tubules, the kidneys have the ability to concentrate it by reabsorbing water. This is important for maintaining proper hydration levels and conserving water when necessary.

5. Formation of urine: After the processes of filtration, reabsorption, and secretion, the final product is the urine. The urine collects in the renal pelvis and then travels down the ureters to the bladder, where it is stored until it is eliminated from the body through the urethra during urination.

Where is the primary urine and where is the secondary urine?

The primary urine, also known as the filtrate, is formed during the filtration process in the glomerulus of the nephrons. It contains water, electrolytes, waste products, and other small molecules that have passed through the filtration barrier. The primary urine then enters the tubules of the nephrons.

As the primary urine flows through the tubules, reabsorption and secretion processes occur, leading to the formation of the secondary urine. The secondary urine is the final product that is excreted from the body as urine. It contains waste products, excess water, and electrolytes that were not reabsorbed back into the bloodstream.

In summary, the primary urine is formed in the glomerulus during filtration, while the secondary urine is formed in the tubules of the nephrons through processes of reabsorption and secretion.