2) Glomerular Filtration & Urine Formation

• What are the three main processes of urine formation?

• Filtration, reabsorption, and secretion.

Where does glomerular filtration occur?

• In the glomerulus, across the filtration membrane into the capsular space.

What are the three layers of the filtration membrane?

• Endothelium of glomerular capillaries, basement membrane, and podocytes with filtration slits.

What are podocytes and what do they form?

Specialized cells with foot processes (pedicels) that create filtration slits.

• What substances normally pass through the filtration membrane?

• Water, glucose, ions, small solutes, and hormones.

•  What substances are normally blocked by the filtration membrane?

 Red and white blood cells, platelets, and large proteins

• Why is reabsorption essential after filtration?

• Prevents loss of vital nutrients like glucose and vitamins in urine.

• What is the role of secretion in urine formation?

Adds wastes (like ions, drugs, toxins) from blood into tubular fluid

• What does the presence of blood in urine indicate?

• Possible damage to the filtration membrane or infection.

• What does significant protein in urine suggest clinically?

Abnormal filtration, often due to kidney damage or disease.