No questions found
(a) Describe how the student could use this procedure to find the water potential of the plant storage tissue that has coloured cell sap.
[8]
(b) (i) Suggest suitable units for the rate of movement of the drop.
[1]
(ii) State how the student would estimate the water potential of the plant tissue.
[2]
(c) (i) Identify the independent and dependent variables in this investigation.
independent
dependent
[2]
(ii) Identify two variables which the student may not have adequately controlled during the investigation.
1.
2.
[2]
(iii) State how one of the variables you have identified in (c)(ii) may have influenced the results.
[1]
(d) The student made direct observations of the cells of the tissues that had been immersed in $0.2 \text{ mol dm}^{-3}$ and $0.8 \text{ mol dm}^{-3}$ sucrose solutions.
(i) Predict the appearance of the cells under the microscope when immersed in $0.2 \text{ mol dm}^{-3}$ sucrose solution
0.8 mol dm$^{-3}$ sucrose solution
[1]
Use the space below for any diagrams you include in your answer to (i).
(ii) Explain your answers to (d)(i).
[2]
540
588
534
(a) (i) Suggest why the mice were treated with FSH before the ovaries were removed.
................................................................................................................................................................................
................................................................................................................................................................................[1]
(ii) Suggest the purpose of keeping the oocytes in a medium that maintains them at the primary oocyte stage.
................................................................................................................................................................................
................................................................................................................................................................................[1]
(b) Explain what $S_{M}$ shows about the mean percentage values.
................................................................................................................................................................................
................................................................................................................................................................................[1]
(c) (i) State the null hypothesis for these tests.
................................................................................................................................................................................
................................................................................................................................................................................[1]
(ii) State a statistical test that could be used and give the reason for your choice.
test .......................................................................................................................................................................
reason for your choice .................................................................................................................................
................................................................................................................................................................................[2]
(iii) The result of the statistical test comparing FF-MAS with 22R-HC at $0.70 \mu mol dm^{-3}$ was significant at 0.05 probability level. Explain what this means.
................................................................................................................................................................................
................................................................................................................................................................................[1]
(d) (i) State whether or not the evidence in Table 2.1 supports the original hypothesis that FF-MAS activates the specific membrane receptor, LXR alpha.
Explain your answer.
................................................................................................................................................................................
................................................................................................................................................................................[1]
(ii) State the conclusions that can be drawn from the results in Table 2.1.
................................................................................................................................................................................
................................................................................................................................................................................
................................................................................................................................................................................
................................................................................................................................................................................
................................................................................................................................................................................[3]
545
519
539
