Assume that an animal consumes 200 ml of O2 in the course of metabolizing 250 mg of food. Determine the probable kind of food the animal has metabolized. How much heat has been produced?

I determined the food type by dividing 200 by 250 to get 0.8 ml O2/mg, which is close to the table value given as 0.84. However, I'm not sure how to calculate the heat produced. This info is given for the food type I chose: cal/mg=4.2, cal/ml O2=5, cal/ml CO2=5. I know it can be calculated with determining O2 consumption, but I don't know how. Please help.

To calculate the heat produced during metabolism, you need to determine the amount of oxygen consumed. The equation for determining oxygen consumption is:

O2 consumed (ml) = Food intake (mg) x O2 utilization ratio (ml O2/mg)

From your calculation, you found that the O2 utilization ratio is approximately 0.8 ml O2/mg. Now, let's calculate the oxygen consumption:

O2 consumed = 250 mg x 0.8 ml O2/mg = 200 ml O2

Given that the animal consumed 200 ml of O2, the heat produced can be calculated by multiplying the oxygen consumption by the heat value for 1 ml of O2:

Heat produced = O2 consumed (ml) x cal/ml O2

From the information provided, cal/ml O2 is given as 5:

Heat produced = 200 ml O2 x 5 cal/ml O2 = 1000 cal

Therefore, the animal has likely metabolized a food type that produces approximately 1000 calories of heat.