During an exercise, a man consumes 1 L of oxygen per minute. The O₂ content of blood in his left ventricle is 183 mL/L, and the O₂ content of blood in his right ventricle is 133 mL/L. His cardiac output during that exercise is

To find the cardiac output, we need to calculate the difference in oxygen content between the left and right ventricles and then use the Fick principle to determine the cardiac output.

First, we find the difference in oxygen content:
Oxygen content difference = Oxygen content in left ventricle - Oxygen content in right ventricle
= 183 mL/L - 133 mL/L
= 50 mL/L

Now, using the Fick principle:
Cardiac output = Oxygen consumption / Oxygen content difference

 $$\begin{gathered} = \frac{1,000 \mathrm{mL}}{min}÷\frac{50 \mathrm{mL}}{\mathrm{L}} \\ = \frac{1,000 \mathrm{mL}}{min}\times \frac{\mathrm{L}}{50 \mathrm{mL}} \\ = 20 \mathrm{L}/\min \end{gathered}$$
 

So, the cardiac output during the exercise is 20 litres per minute.