The primary nitrogen-containing compound excreted by our kidneys is __________.

• A. uric acid
• B. amino acids
• C. ammonia
• D. nitrite
• E. urea

Answer: (E)

Verified step by step guidance

1. Understand the role of the kidneys in the human body: The kidneys are responsible for filtering waste products from the blood and excreting them in the form of urine.
2. Identify the main nitrogenous waste products: In humans, the primary nitrogenous waste products include urea, uric acid, ammonia, and creatinine.
3. Recognize the primary nitrogen-containing compound excreted by the kidneys: Urea is the main nitrogenous waste product excreted by the kidneys in humans.
4. Learn why urea is the primary excreted compound: Urea is produced in the liver through the urea cycle, which converts ammonia, a toxic byproduct of protein metabolism, into urea, which is less toxic and can be safely excreted by the kidneys.
5. Differentiate urea from other nitrogenous compounds: While uric acid, ammonia, and other compounds are present in the body, urea is the most abundant and primary nitrogen-containing compound excreted by the kidneys.