The ______ are the functional units of the kidneys that process filtrate and produce urine.

• A. nephrons
• B. ureters
• C. glomeruli
• D. renal pyramids

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by understanding the anatomy of the kidney. The kidney is composed of several structures, including the renal cortex, renal medulla, renal pyramids, and renal pelvis. Its primary function is to filter blood and produce urine.
2. Step 2: Learn about the functional units of the kidney. The nephrons are microscopic structures within the kidney responsible for filtering blood, reabsorbing essential substances, and excreting waste products as urine.
3. Step 3: Differentiate between the options provided. Nephrons are the functional units of the kidney, while ureters are tubes that transport urine from the kidneys to the bladder. Glomeruli are part of the nephron, specifically the capillary network involved in filtration. Renal pyramids are structures within the medulla that contain collecting ducts but are not functional units themselves.
4. Step 4: Understand the process of urine formation. Nephrons consist of the glomerulus and tubules, which work together to filter blood, reabsorb water and nutrients, and concentrate waste into urine.
5. Step 5: Based on the explanation, identify the correct answer as 'nephrons,' since they are the functional units of the kidney responsible for processing filtrate and producing urine.