Nutrients and food testsIB MYP Biology: Subtopic test

1. 1
   A 15-year-old girl in Doha eats very little red meat or green vegetables. She feels tired all the time, and her doctor finds that she has anaemia.

   (a)

   A lack of which mineral is the most likely cause of her anaemia?

   [1 mark]

   • ACalcium
   • BFibre
   • CIron
   • DVitamin C

   (b)

   Which of these foods is the best source of iron?

   [1 mark]

   • ABeef
   • BButter
   • COrange juice
   • DWhite rice

   (c)

   Explain why a lack of iron makes the girl feel tired.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   Sailors on long sea voyages in the 1700s, who ate no fresh fruit, often developed bleeding gums and wounds that would not heal. Today, some children whose diets contain too little vitamin D develop soft, bent leg bones.

   (a)

   Which deficiency disease affected the sailors in the 1700s?

   [1 mark]

   • ARickets
   • BScurvy
   • CKwashiorkor
   • DAnaemia

   (b)

   Which nutrient is lacking in the diets of the children with soft, bent leg bones?

   [1 mark]

   • AVitamin C
   • BIron
   • CFibre
   • DVitamin D

   (c)

   Explain why a diet low in vitamin D leads to soft bones.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A student has four unlabelled food samples, W, X, Y and Z, each mixed with water. She tests each one with iodine solution, with Benedict's solution (heated in a water bath), with biuret solution, and with the ethanol emulsion test. Sample W turns blue-black with iodine and gives no other change. Sample X turns brick-red with Benedict's solution and purple with biuret solution, and gives no other change. Sample Y gives a cloudy white layer in the ethanol emulsion test and no other change. Sample Z gives no change in any test.

   (a)

   State the nutrient or nutrients present in samples W, X and Y.

   [3 marks]

   (b)

   Describe how the student could check that sample X contains protein, including one safety precaution.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A school science club in Dubai wants to compare the energy in a crisp and in a dried date, because the canteen sells both. The school is also worried that more students are becoming overweight.

   (a)

   Describe how the science club could compare the energy in the crisp and the date by burning them, and suggest one way to make the results more accurate.

   [6 marks]

   (b)

   Discuss and evaluate whether the school should ban crisps and other snacks that are high in fat and sugar from its canteen.

   [6 marks]

   Total for question 4: 12 marks

End of questions