Question

What is the first step in the formation of urine?

Answer 1

Urine:

1. Urine is a liquid by-product obtained from metabolism in humans and other animals.
2. Common color of urine is from pale yellow to deep amber because of pigment urochrome.
3. The color depends on the food and medications which are taken into the body.
4. Urine flows from the kidneys through the ureters to the urinary bladder.
5. Urination results in urine being excreted from the body through the urethra.

Formation of urine:

1. The formation of urine has three processes.
2. The three processes are glomerular filtration, reabsorption, and secretion.
3. These processes occur in various parts of the nephron.

Glomerular filtration:

1. The first step is glomerular filtration.
2. Glomerular filtration is filtrating blood carried out by the glomerulus.
3. About 1200 ml of blood is filtered by the kidney per minute.
4. It occurs when blood enters the glomerulus through an afferent arteriole.
5. Due to glomerular blood pressure, the water and small solutes move from the glomerulus to the glomerular capsule.
6. The large molecules and formed elements are unable to pass through the capillary wall.
7. The filtered fluid is protein-free and is devoid of cells.
8. The filterability of solutes is inversely proportional to their size.