Which process primarily occurs at the glomerulus within the nephron?

• A. Concentration
• B. Reabsorption
• C. Filtration
• D. Secretion

Answer: (C)

Verified step by step guidance

1. Understand the structure and function of the nephron: The nephron is the functional unit of the kidney, responsible for filtering blood and forming urine. It consists of several parts, including the glomerulus, proximal tubule, loop of Henle, distal tubule, and collecting duct.
2. Focus on the glomerulus: The glomerulus is a network of capillaries located within the Bowman's capsule. Its primary role is to filter blood, separating water, ions, and small molecules from larger proteins and blood cells.
3. Define filtration: Filtration is the process by which blood plasma and small solutes pass through the glomerular capillaries into the Bowman's capsule, forming the filtrate. This process is driven by hydrostatic pressure within the glomerular capillaries.
4. Differentiate filtration from other processes: Concentration, reabsorption, and secretion occur in other parts of the nephron, such as the proximal tubule, loop of Henle, and distal tubule. Filtration is unique to the glomerulus and is the first step in urine formation.
5. Conclude that filtration is the correct process occurring at the glomerulus: The glomerulus is specialized for filtration, which is essential for removing waste products and excess substances from the blood while retaining larger molecules like proteins and cells.