AQA Biology question help URGENTWatch this thread
Volume of oxygen absorbed by the gills from each dm3 of water /cm3 = 7
Mass of fish / kg = 0.4
Oxygen required by fish / cm3 kg–1 hour–1 = 90
(i) Calculate the volume of water that would have to pass over the gills each hour
to supply the oxygen required by the fish. Show your working.
Can anyone tell me how to work out this question.
Correct answer of 5.1 or 5.14 (dm3) = 2 marks;
One mark for incorrect answers that show 36 or 0.4 x 90 or 90 ÷ 7;
Fish weighs 0.4kg, so 0.4 x 90 = 36cm3 O2 needed per hour
7cm3 of O2 per dm3 water,
so 36cm3 / 7cm3 = 5.14... dm3 water
Could you please explain why you did each step.
I think the 0.4 x 7 is to see the oxygen required for THIS fish but I don't understand why you divided it by 7 after that?