0 1 The nucleus of a cell contains DNA.
0 1 . 1 Name the structures inside the cell nucleus that contain DNA.
[1 mark]
Figure 1 shows part of a DNA
... [Show More] molecule.
Figure 1
0 1 . 2 Name the part of the DNA molecule labelled X.
[1 mark]
0 1 . 3 What type of substances are labelled A, C, G and T in Figure 1?
[1 mark]
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Figure 2 shows another section of a DNA molecule. box
Figure 2
Four of the substances you named in Question 01.3 are not labelled in part Y
of Figure 2.
Label each of these substances with the correct letter, A, C, G or T.
Use information from other parts of Figure 2 to help you.
[1 mark]
0 1 . 4
0 1 . 5 What is happening to the DNA in part Z of Figure 2?
[1 mark]
Tick () one box.
Differentiation
Evolution
Fertilisation
Replication
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0 1 . 6 A gene is a length of DNA.
What type of substance does a gene code for?
[1 mark]
0 1 . 7 Most human body cells contain 6 × 10–12 grams of DNA.
What mass of DNA will a human sperm cell contain?
[1 mark]
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6 × 10–6 grams
6 × 10–12 grams
3 × 10–6 grams
3 × 10–12 grams
0 1 . 8 What is the name of the type of cell division that produces sperm cells?
[1 mark]
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Binary fission
Differentiation
Meiosis
Mitosis
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box 0 2 A student investigated the effect of temperature on the decay of milk.
Figure 3 shows the apparatus the student used.
Figure 3
This is the method used.
1. Set up the apparatus as shown in Figure 3 with the milk at 20 °C.
2. Record the pH over 5 days using the computer.
3. Repeat with another batch of fresh milk at 25 °C.
0 2 . 1 How could the student keep the milk at a constant temperature for 5 days?
[1 mark]
0 2 . 2 Give one variable the student should keep constant.
Do not refer to temperature in your answer.
[1 mark]
Question 2 continues on the next page
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Table 1 shows the student’s results for the milk at 20 °C.
Table 1
Time in days 0 1 2 3 4 5
pH 6.7 6.7 6.3 5.3 4.6 4.4
0 2 . 3 Complete Figure 4.
[4 marks]
You should:
• label the x-axis
• use a suitable scale for the x-axis
• plot the data from Table 1
• draw a line of best fit.
Figure 4
0 2 . 4 The data you plotted in Question 02.3 were obtained at 20 °C.
Sketch a line on Figure 4 to show the results you would expect at 25 °C.
Label this line ‘25 °C’. [Show Less]