<prompt> Which of the following true about ventilation and perfusion in alveoli in erect posture?Ventilationperfusion ratio is maxm at apexVentilationperfusion ratio is maxm at baseVentilation is max at apexPerfusion is max at apex  <response>: The VQ ratio can therefore be defined as the ratio of the amount of air reaching the alveoli per minute to the amount of blood reaching the alveoli per minute--a ratio of volumetric flow rates. ... The VQ ratio can be measured with a ventilationperfusion scan. A VQ mismatch can cause a type 1 respiratory failure Ref: guyton and hall textbook of medical physiology 12 edition page number: 320,321,322 