Nutrition and balanced dietIB MYP Sciences: Subtopic test

1. 1
   A school canteen in Dubai is redesigning its lunch menu so that students get a range of nutrient groups. Menu items include a chicken and rice bowl, buttered toast, an orange and a bean salad.

   (a)

   Which nutrient group is needed mainly for growth and repair of body tissues?

   [1 mark]

   • ACarbohydrate
   • BFibre
   • CProtein
   • DWater

   (b)

   Which nutrient group releases the most energy per gram when it is used in respiration?

   [1 mark]

   • ACarbohydrate
   • BProtein
   • CVitamins
   • DFat (lipid)

   (c)

   Explain why fibre is an important part of a balanced diet.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A student in Auckland is given an unknown food sample, mixed with water, and carries out three tests. With iodine solution the sample turns blue-black. After heating with Benedict's solution it stays blue. With biuret reagent it stays blue.

   (a)

   What can be concluded from the iodine test result?

   [1 mark]

   • AStarch is present
   • BProtein is present
   • CReducing sugar is present
   • DFat is present

   (b)

   Which result would have shown that a reducing sugar was present?

   [1 mark]

   • AA blue-black colour with iodine
   • BA brick-red precipitate after heating with Benedict's solution
   • CA purple colour with biuret reagent
   • DA cloudy white emulsion with ethanol and water

   (c)

   Describe how the student could test the sample for protein, and the result that would show protein is present.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   On long sea voyages in the 18th century, many sailors developed bleeding gums, extreme tiredness and wounds that would not heal. Their diet was mostly dried biscuits and salted meat. When ships began to carry limes, the sailors recovered and the symptoms disappeared.

   (a)

   Identify the deficiency disease the sailors had and explain why eating limes cured it.

   [3 marks]

   (b)

   Outline how a lack of iron and a lack of vitamin D can each harm health.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A student in Nairobi notices that ripe bananas taste much sweeter than unripe ones. She suggests that ripe bananas contain more reducing sugar than unripe bananas, because starch is changed into sugar as the fruit ripens. In her class discussion, her teacher points out that several governments, including the UAE, place a tax on sugary drinks to improve public health.

   (a)

   Design an investigation to test the student's suggestion that ripe bananas contain more reducing sugar than unripe bananas.

   [6 marks]

   (b)

   Discuss and evaluate the use of a tax on sugary drinks as a way to improve public health.

   [6 marks]

   Total for question 4: 12 marks

End of questions