Nitrate is consumed and eventually taken up by the ________ in the _________.

Nitrate is consumed and eventually taken up by the ________ in the _________.

• A. Intestines; bloodstream
• B. Lungs; alveoli
• C. Stomach; lumen
• D. Kidneys; pelvis

Answer: (A)

Absorption of dietary nitrate happens across the intestinal lining into the bloodstream. After you ingest nitrate, it is taken up by the intestinal mucosa—primarily in the small intestine—and enters the blood, traveling through the portal circulation to the liver and then into systemic circulation. This makes the intestines and bloodstream the correct pair. The lungs and alveoli handle gas exchange, the stomach lumen is a hollow space rather than the uptake site for nitrate into blood, and the kidneys/pelvis relate to filtration and excretion rather than initial uptake of dietary nitrate into circulation.

Absorption of dietary nitrate happens across the intestinal lining into the bloodstream. After you ingest nitrate, it is taken up by the intestinal mucosa—primarily in the small intestine—and enters the blood, traveling through the portal circulation to the liver and then into systemic circulation. This makes the intestines and bloodstream the correct pair. The lungs and alveoli handle gas exchange, the stomach lumen is a hollow space rather than the uptake site for nitrate into blood, and the kidneys/pelvis relate to filtration and excretion rather than initial uptake of dietary nitrate into circulation.