IGCSE Biology Paper 6 · Alternative to Practical practice papers
Core & Extended · 4 questions, Q4 = planning. Each generated paper follows the 0610 Paper 6 · Alternative to Practical format, with the same number and style of questions as the real exam, and comes with a Cambridge-style mark scheme.
Alternative to Practical papers have four questions: reading instruments, completing a results table, plotting and using a graph, and a final planning question. On the harder settings, each question adds the evaluation parts that decide top grades, such as which way an error moves a result and why each step of a method is needed.
Add Benedict’s solution to the food solution; heat in a water bath at about 80 °C for a few minutes
Add (equal volume of) Benedict’s solution B1 Heat in a (hot) water bath B1
2
(c)
Wear eye protection / use a water bath, not a direct flame
Eye protection / water bath / tongs/test-tube holder B1
1
Question 2Structured · 12 marks
A student investigates the effect of temperature on the activity of amylase. Starch and amylase are mixed at each temperature. A drop of the mixture is tested with iodine solution every 10 s until the iodine stays orange-brown. Fig. 2.1 shows the stopwatch reading at 20 °C.
Fig. 2.1
(a)
Record the time shown in Fig. 2.1, to the nearest 10 s.
[1]
(b)
Calculate the rate of reaction (1000 ÷ time) for each temperature and complete Table 2.1.
temperature / °C
time for starch to be digested / s
rate / s−1
10
not digested after 600 s
0
20
30
80
40
60
50
210
60
not digested after 600 s
0
Table 2.1
[2]
(c)
Plot a graph of rate (y-axis) against temperature (x-axis). Join the points with a smooth curve.
Fig. 2.2
[4]
(d)
Explain the result at 60 °C.
[2]
(e)
Suggest how the student could find the optimum temperature more accurately.
[1]
(f)
State two variables the student should control.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
210 s
210 B1
1
(b)
0, 4.76, 12.5, 16.7, 4.76, 0
All rates correct B1 Consistent decimal places B1
2
(c)
See graph
Axes labelled with quantity and unit, rate / s−1 on the y-axis and temperature / °C on the x-axis; suitable scales so the points occupy at least half the grid B1 All points plotted correctly to within half a small square (B1 for at least four correct) B2 Single, thin, well-judged best-fit line (or smooth curve) B1
4
(d)
Amylase is denatured; active site changes shape so starch cannot bind
denatured B1 active site shape changed / starch cannot fit B1
2
(e)
Repeat using smaller temperature intervals between 30 °C and 50 °C
Smaller intervals around the peak B1
1
(f)
Volume/concentration of starch; volume/concentration of amylase; pH
Any two: starch concentration/volume, amylase concentration/volume, pH B2
2
Question 3Structured · 11 marks
Fig. 3.1 shows two leaves, P and Q, from different species of plant. (Print at 100% so that measurements are accurate.)
Fig. 3.1
(a)
Make a large drawing of leaf P.
[4]
(b)(i)
Measure the length of line AB on Fig. 3.1.
[1]
(ii)
Draw a line on your drawing in the same position as AB. Measure this line and calculate the magnification of your drawing. Show your working.
[3]
(c)
Describe three visible differences between leaf P and leaf Q.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
Large, accurate drawing
Clear, continuous outline (no sketchy lines or shading) B1 Drawing larger than Fig. 3.1 and occupies at least half the space B1 Correct proportions, e.g. length : width B1 Detail: midrib and veins / petiole shown B1
4
(b)(i)
28 mm (±1 mm)
28 ± 1 B1
1
(ii)
length of line on drawing ÷ AB
Line drawn and measured correctly on drawing B1 Their length ÷ 28 M1 Correct answer, no units, to an appropriate number of significant figures A1
3
(c)
P has a smooth margin, Q serrated; Q longer and narrower; Q has a longer petiole
Margin: P smooth / Q serrated (toothed) B1 Shape: Q longer and narrower / P broader B1 Petiole (stalk) longer in Q B1
3
Question 4Structured · 11 marks
A student investigates the effect of light intensity on the rate of photosynthesis in pondweed by counting the bubbles released in one minute at different distances from a lamp (Fig. 4.1). Each count is repeated three times.
Fig. 4.1
(a)
Complete Table 4.1 by calculating the mean number of bubbles for each distance.
distance / cm
count 1
count 2
count 3
mean bubbles per minute
10
79
78
79
20
23
21
20
30
10
8
11
40
3
3
3
50
5
1
3
Table 4.1
[2]
(b)
Plot a graph of mean number of bubbles (y-axis) against distance (x-axis). Draw a smooth curve.
Fig. 4.2
[4]
(c)
Describe and explain the results.
[3]
(d)
Suggest why counting bubbles may not be an accurate way to measure the rate.
[1]
(e)
Suggest how temperature could be kept constant.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
78.7, 21.3, 9.7, 3.0, 3.0
All means correct B1 Consistent to 1 d.p. B1
2
(b)
See graph
Axes labelled with quantity and unit, mean bubbles per minute on the y-axis and distance / cm on the x-axis; suitable scales so the points occupy at least half the grid B1 All points plotted correctly to within half a small square (B1 for at least four correct) B2 Single, thin, well-judged best-fit line (or smooth curve) B1
4
(c)
As distance increases, the rate decreases; light intensity decreases with distance; light is the limiting factor
As distance increases, number of bubbles decreases B1 Light intensity decreases as distance increases B1 Light intensity is limiting B1
3
(d)
Bubbles are different sizes / hard to count
Bubbles different sizes or too fast to count B1
1
(e)
Use a water bath or a heat shield (glass of water) between the lamp and the beaker; use an LED lamp
Riyaz Shaikh has mentored IGCSE, IB and A Level students for 15+ years, one-on-one, online and in Mumbai. The hardest questions on this site are the ones he uses to find a student's weak points.
Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in