IGCSE 2020 Biology 0610/62 Feb/Mar

IGCSE 2020 0610/62 Feb/Mar (pdf)

• Show Video with Step-by-Step Solutions

1. (a) Beetroot is the large fleshy root of a beet plant. The cells of beetroot contain a coloured pigment. This pigment may leak from the cells if the cell membranes are damaged.
   A student investigated the effect of temperature on the leakage of pigment from beetroot cells.
   Step 1 Cylinders of varying length were cut from a beetroot. The student was provided with two of the beetroot cylinders. The student cut both cylinders to 3cm in length.
   Step 2 The student labelled one test-tube C and another test-tube H.
   Step 3 The student put some cold water into test-tube C and some hot water into test-tube H.
   Step 4 The student measured the temperature of the water in test-tube C and in test-tube H. Sections of the thermometers are shown in Fig. 1.1.
   Step 5 The student put one beetroot cylinder into test-tube C and one beetroot cylinder into test-tube H. A stopper was placed in each test-tube.
   Step 6 The student waited for 10 minutes.
   Step 7 After 10 minutes the student shook both test-tubes.
   Step 8 The student observed the colour of the liquid in both test-tubes.
   The student’s observations are shown in Fig. 1.2.
   (i) Prepare a table to record the results shown in Fig. 1.1 and Fig. 1.2.
   (ii) State a conclusion for these results.
   (iii) In step 1 the two beetroot cylinders were cut to the same length.
   Suggest why this was necessary.
   (iv) Identify one possible source of error in step 3.
   Suggest a piece of apparatus that could be used to reduce this error.
   (v) In step 7 the student shook the test-tubes. It was important that the shaking of both test- tubes was the same.
   Suggest two ways that this could be achieved.
   (vi) Estimate the percentage of light passing through the liquid at 50°C.
   Show on your graph how you obtained your estimate.

2. Fig. 2.1 is a photograph of a leaf from a beet plant.
   (a) (i) Make a large drawing of the leaf shown in Fig. 2.1.
   (ii) Measure the length of the line PQ on Fig. 2.1. Include the unit.
   length of line PQ ……..
   Calculate the actual length of the leaf using the formula and your measurement.
   magnification = length of line PQ/actual length of the leaf
   Give your answer to the nearest whole number and include the unit. Space for working.
   (b) Some athletes drink beetroot juice because they think it improves their performance.
   Scientists investigated the effect of drinking 100cm3 of beetroot juice on the length of time that athletes were able to run at their fastest pace before stopping due to exhaustion.
   The results of the investigation are shown in Fig. 2.2.
   (i) Explain why a control group was used in this investigation.
   (ii) Suggest a suitable control experiment for this investigation.
   (iii) Calculate the percentage increase in the average time athletes were able to run for the beetroot group compared to the control group.
   Give your answer to one decimal place.
   (c) An athlete suggested the hypothesis:
   ‘Drinking a greater volume of beetroot juice would increase the length of time that athletes are able to run.’
   Plan an investigation to test this hypothesis.
   (d) Athletes often consume energy drinks.
   Describe how you could test a sample of an energy drink to determine if reducing sugars are present.

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.