No questions found
(a) (i) Complete Fig. 1.1 to show how you will make three further concentrations of glucose solution, G.
[3]
(ii) Complete Table 1.1 to show the volumes of solutions you intend to use in your investigation.
Table 1.1
| solution | volume / cm^3 |
|-------------|---------------|
| Benedict's | |
| each concentration of G |
| S1 | |
| S2 | |
[2]
(b) (i) State one variable, other than the volume of each solution, which needs to be kept the same in this investigation. Describe how you will keep this variable the same.
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[1]
(b) (ii) Prepare the space below and record your results.
(c) (i) Estimate the concentration of glucose in solutions S1 and in S2.
S1 ..........................................................
S2 ..........................................................
[1]
(c) (ii) State which solution, S1 or S2, is most likely to be from an untreated diabetic.
untreated diabetic ....................................................
[1]
585
586
566
The diameter of a tube, which carries urine in a mammal, was measured at different distances along its length. The diameter of the tube was found to vary along its length.
The results are shown in Table 2.1.
Table 2.1
[Table_1]
(a) (i) Plot a graph of the data shown in Table 2.1.
Fig. 2.1 is a photomicrograph of the transverse section through this tube.
Fig. 2.1
(b) (i) Calculate the actual diameter of the tube shown by line X in Fig. 2.1.
You may lose marks if you do not show your working or if you do not use appropriate units.
[4 marks]
(ii) Use the actual diameter of the tube calculated in (ii) and your graph in (a)(i) to estimate the distance along the length of the tube, where the section was cut.
...........................................................[1 mark]
(iii) Describe how you would find the mean diameter of the tube shown in Fig. 2.1.
...........................................................[2 marks]
Fig. 2.2 is a photomicrograph of a transverse section of a different tube from a mammal.
Fig. 2.2
(iv) Prepare the space below so that it is suitable for you to record the observable differences between the specimens in Fig. 2.1 and in Fig. 2.2.
Record your observations in the space you have prepared.
545
589
514
L1 is a slide of a stained transverse section through a stem.
(a) (i) Draw a large plan diagram of the whole of the transverse section.
Label the epidermis and xylem.
[5]
(ii) Calculate the ratio of the total diameter of the stem to the diameter of the central pith.
You may lose marks if you do not show your working or if you do not use appropriate units.
[1]
(b) (i) State one observable feature of the epidermis that supports the conclusion that this is a stem from a plant growing in a dry habitat.
Explain how this feature reduces water loss.
feature ..........................................................................................................................
explanation ..................................................................................................................
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[1]
(ii) Make a large drawing of three adjacent (touching) cells from the central pith.
Label the cell wall.
[5]
581
523
515
