Question

Which is not part of glomerular ultrafiltrate ?

• A. Glucose
• B. RBC
• C. Amino acids
• D. Minerals

Answer 1

The Correct Option is B

Urine formation is a three-step process that occurs within nephrons, the small filtration units in the kidney.
 The steps involved are:
1. Glomerular filtration, 
2. Reabsorption, and 
3. Secretion.

• Glomerular filtration is the initial step, where blood passes through the glomerular part of the nephron. This process involves blood passing through three layers: the endothelium of glomerular blood vessels, the epithelium of Bowman’s capsule, and the basement membrane between these layers.
• The epithelium of Bowman’s capsule contains minute pores that filter every constituent from plasma through its membrane, with the exception of larger molecules such as proteins and red blood cells. This filtration process is known as ultrafiltration, and the resulting fluid is called glomerular ultrafiltrate.
• Glomerular ultrafiltrate does not contain large molecules like red blood cells but includes smaller molecules such as glucose, amino acids, and minerals. These smaller molecules can easily pass through the epithelium of Bowman’s capsule, thus becoming part of the ultrafiltrate.
• Subsequently, nearly 99% of glomerular ultrafiltrate is reabsorbed by renal tubules. The remaining fluid, which contains waste materials for excretion, is referred to as urine.