Describe the limitations of using a change in mass as a measure of osmosis.

Finding the mean water potential of potato tuber cells and carrying semi-quantitative tests for reducing sugars

⦁ DISCUSSION

This section will include an interpretation of your results written in full sentences and paragraphs. It should include a description of trends and a discussion of the findings in light of the biological concepts involved (e.g. osmosis and water potential theory).

It should also include comments on sources of error, limitations in the data, assumptions made by the investigator about the system and ideas for further investigation.

Things to consider:

⦁ What caused the differences in weight of the tubers before and after they had been in the solutions? Discuss relative water potentials and use the key terms – isotonic, hypotonic and hypertonic.

⦁ Describe the limitations of using a change in mass as a measure of osmosis.

⦁ What sources of error were there?

⦁Compare and reference other results from the same or related experiments.

⦁ What could you have done to improve your investigation?

For example…

…the differences between the solutions were large – could you really pinpoint the exact water potential from your results? If not, what could you do differently?

…ensuring the surface area of the potato tubers were the same, having a more consistent method for blotting off excess water,

…did we give the cells enough time in the solutions to change in mass?

…did we do sufficient repeats?

…how could we check if the tuber cells are representative of all potato cells? E.g. by comparing these to results from other potatoes

⦁ What practical applications can you think of for this experiment? What further investigations come to mind?

⦁ CONCLUSIONS

Write a brief and clear statement that relates to your hypothesis/experiment aims:

⦁ Were the aims of the experiment met (which you have)

⦁ What where the main findings (no explanation why needed here)

⦁ REFERENCES

List your sources of information

If you used any websites, textbooks or other resources when writing your introduction and discussion, list them here following standard referencing outlines.

 

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