Which of the following statement(s) is/are true concerning oxygen consumption (O2)?

a. O2 is normally 100–120 cc2/m2/min

b. Resting O2 is controlled by the level of thyroid and catecholamine hormones

Oxygen consumed in the process of metabolism is expressed as the volume of oxygen per minute (O2). O2 is normally 100– 120 cc2/m2/min, or 200 cc/min for a typical adult. Resting O2 is a function of metabolizing body cell mass, with fine tuning control provided by the level of thyroid and catecholamine hormones. O2 decreases under conditions of hypothermia, paralysis, and hypothyroidism. O2 increases during exercise or muscular activity, hyperthermia, profound hypothalamic injury, hyperthyroidism, catecholamines, and inflammatory mediators, particularly the interleukin cytokines. Under steady state conditions, the amount of oxygen consumed in systemic metabolism is exactly equal to the amount of oxygen taken up by the pulmonary capillaries via the airway. This is true regardless of the status of pulmonary function or dysfunction, so we measure O2 across the lung and assume that it is exactly the amount consumed in the systemic metabolism.