Biology 0610/61 October/November 2024: question paper and mark scheme

Question

A student investigated the movement of water across a membrane by osmosis. Dialysis tubing is made from a type of membrane that is partially permeable. Only small molecules such as water can pass through this membrane. The student used this method: Step 1 Label two test-tubes S and W. Step 2 Put 20 cm3 of distilled water into each of the labelled test-tubes. Step 3 Take a piece of dialysis tubing and knot it at one end to form a bag. Step 4 Put 6 cm3 of sucrose solution into the open end of the dialysis tubing bag. Step 5 Rinse the outside of the dialysis tubing bag with distilled water. Step 6 Use a ruler to measure the distance from the knot at the bottom of the dialysis tubing bag to the bottom of the meniscus in the bag, as shown in Fig. 1.1. finger and thumb holding the dialysis tubing bag bottom of the meniscus distance to measure knotted end Fig. 1.1 Step 7 Place the dialysis tubing bag into test-tube S. Fold the open end of the bag over the top of the test-tube. Use an elastic band to hold the dialysis tubing in place, as shown in Fig. 1.2. top of the open end of the dialysis elastic band tubing bag folded over sucrose solution dialysis tubing bag distilled water knotted end test-tube Fig. 1.2 Step 8 Repeat steps 3 to 7 using test-tube W and 6 cm3 of distilled water instead of sucrose solution in step 4. Step 9 Place both test-tubes into a hot water-bath for 15 minutes. Step 10 After 15 minutes, remove test-tubes S and W from the hot water-bath and put them into a test-tube rack. Step 11 Remove the dialysis tubing bag from test-tube S. Use the ruler to re-measure the distance from the knot at the bottom of the dialysis tubing bag to the bottom of the meniscus in the bag. Step 12 Repeat step 11 with test-tube W. (a) Fig. 1.3 shows the student’s dialysis tubing bags from test-tubes S and W at 0 minutes and 15 minutes. dialysis tubing bag from test-tube S dialysis tubing bag from test-tube W 0 minutes 15 minutes 0 minutes 15 minutes Fig. 1.3 (i) Measure the distance from the knot at the bottom of the dialysis tubing bag to the bottom of the meniscus in the bag for all four dialysis tubing bags shown in Fig. 1.3. (Fig. 1.1. shows where the measurements should be taken on the dialysis tubing bags.) Prepare a table and record your measurements from Fig. 1.3 in your table. [3] (ii) Calculate the change in distance from the knot to the meniscus of the solution in the dialysis tubing bag in test-tubes S and W. S …… mm W …… mm [1] (iii) State a conclusion for this investigation. …… [1] (b) (i) Suggest a suitable piece of equipment that could be used to measure the distilled water in step 2. …… [1] (ii) Suggest why the dialysis tubing bag was rinsed in step 5. …… [1] (iii) Explain why water was used instead of sucrose solution in the dialysis tubing bag in test-tube W. …… [1] (iv) Identify two variables that were kept constant in this investigation. 1 …… 2 …… [2] (v) This investigation was only done once. Explain why it is better to repeat an investigation. …… [1] (vi) Suggest an alternative method of measuring the movement of water in dialysis tubing bags. …… [1] (c) Sucrose is made from glucose and fructose. Glucose and fructose are reducing sugars. Describe how you could test for the presence of reducing sugars. …… [2] [Total: 14]

Question

In plants, water moves up the stem in xylem vessels as a column of water molecules as a result of transpiration. A celery stalk that still has its leaves attached can be used to investigate the movement of water in a plant, as shown in Fig. 2.1. Fig. 2.2 shows dye in the xylem vessels of a celery stalk. not to scale Plan an investigation to determine the effect of temperature on the rate of movement of a coloured dye through celery stalks. …… [6]

Question

(a) Fig. 3.1 is a photograph of a banana borer insect which is a pest of banana plants. A B magnification ×8 Fig. 3.1 Line AB represents the length of the banana borer. Measure the length of line AB in Fig. 3.1. length of line AB …… mm Calculate the actual length of the banana borer using the formula and your measurement. length of line AB in Fig. 3.1 magnification = actual length of the banana borer Give your answer to two significant figures. Space for working. …… mm [3] (b) Fig. 3.2 is a photograph of one leaf from a banana plant. magnification ×0.04 Fig. 3.2 Fig. 3.3 is a photograph of one leaf from a strawberry plant. magnification ×1.3 Fig. 3.3 (i) Identify three ways the strawberry plant leaf in Fig. 3.3 differs from the banana plant leaf in Fig. 3.2. difference 1 …… difference 2 …… difference 3 …… [3] (ii) Leaves release carbon dioxide gas during respiration. State the name of an indicator that is used to test for the presence of carbon dioxide gas. …… [1] (c) Fig. 3.4 shows a banana flower. Fig. 3.4 Draw a large diagram of the banana flower shown in Fig. 3.4. [4] (d) Bananas contain protein. A student investigated the protein content in different types of fruit. Table 3.1 shows the student’s results. Table 3.1 protein content type of fruit / g per 100 g of fruit apple 0.3 apricot 1.4 avocado 2.0 banana 1.1 guava 2.6 passion fruit 2.2 pineapple 0.9 (i) Calculate the mass of guava that a person would need to eat to gain 14.5 g of protein. Give your answer to the nearest whole number. Space for working. …… g [2] (ii) Plot a bar chart on the grid of the data in Table 3.1. [4] (iii) State the dependent variable in the investigation described in 3(d). …… [1] (e) Samples of three different types of food were labelled X, Y and Z. The samples were tested for protein and starch. The food tests showed that: • Food X contained both protein and starch. • Food Y contained starch only. • Food Z contained protein only. Complete Table 3.2 to show the expected final colours of these food tests. Table 3.2 type of food protein test final colour starch test final colour X Y Z [2] [Total: 20]