Perfusion is defined as?

• A. Perfusion
• B. Circulation
• C. Metabolism
• D. Respiration

Answer: (A)

Perfusion is the flow of blood through the capillary networks to the tissues, delivering oxygen and nutrients and removing wastes. This tissue-level blood flow shows how well the circulation reaches cells to keep them functioning.

Why this matters: perfusion focuses on the actual delivery of blood to the tissues, not just the heart’s pumping or the overall movement of blood. Circulation describes the entire system moving blood through the heart and vessels, which is broader. Metabolism is about the chemical reactions inside cells, producing energy. Respiration involves gas exchange, mainly oxygen in and carbon dioxide out. So the flow of blood to the tissues best captures what perfusion means.