Each nephron is made up of capillaries that form the _.
A. ureter
B. bladder
C. glomerulus
D. sweat glands
The correct answer and explanation is:
The correct answer is C. glomerulus.
The nephron is the functional unit of the kidney, responsible for filtering blood and forming urine. Each nephron consists of a renal corpuscle and a renal tubule. The renal corpuscle contains the glomerulus, a network of tiny capillaries where blood filtration begins.
Blood enters the nephron through the afferent arteriole and flows into the glomerulus. The glomerulus acts as a filtration system, allowing water, small molecules, and waste products to pass through its thin capillary walls. These substances enter the Bowman’s capsule, a cup-shaped structure surrounding the glomerulus. Larger molecules, such as proteins and blood cells, remain in the bloodstream because they are too large to pass through the glomerular capillaries.
The filtered liquid, known as glomerular filtrate, then moves into the renal tubule, where further processing occurs to reabsorb useful substances (such as glucose and ions) and secrete waste products. This process ultimately leads to the formation of urine, which exits the kidneys through the ureter, stored in the bladder, and is excreted through the urethra.
The glomerulus plays a critical role in kidney function by initiating the filtration process that helps maintain fluid and electrolyte balance, remove waste products, and regulate blood pressure. The function of the glomerulus can be compromised in various kidney diseases, such as glomerulonephritis, where inflammation of the glomerular capillaries reduces filtration capacity. This can result in the presence of blood or protein in the urine and impaired kidney function.