<prompt> In an adult man,there is about how much grams of hemoglobin in the circulating blood3505009001000  <response>: PURPOSE: A standardized carbon monoxide CO rebreathing procedure with measurements of CO-hemoglobin, hemoglobin concentration , and hematocrit Hct enables to determine total Hb mass Hbtot, blood, erythrocyte, and plasma volume BV, EV, and PV. These calculations are normally based on venous blood samples. However, micromethods also allow determinations from capillary blood. METHODS: The accuracy of using capillary blood for Hbtot, BV, EV, and PV determination was evaluated in 42 men age: 25.1 - 4.0 yr, body mass: 80.3 - 9.6 kg by comparison of capillary and venous data. RESULTS: Capillary Hbtot 962 - 110 g Ref Robbins 9e pg 420 and internet 