Name: .....................................................................
Date:
D: ____ E:____ F: ___
MYP Assessment
Biology
Title: Investigation into the effects of sugar solution on potato
cells.
Naseem International School
Topic: Cells and Life Processes
Unit Question: What impact have scientific creations had
on individuals, society and the world?
AOI: Human Ingenuity
Grade: 9
D – scientific investigation
MYP Assessment Criteria
E- Data Processing
F - Attitudes in Science
Date assigned:
Time: 4 Lessons
Date due:
Learning objectives linked to the investigation:
Diffusion:
–
–
–
–
–
–
–
Molecules move from a high concentration to a lower concentration by diffusion.
The greater the difference in concentration, the faster the rate of diffusion.
Food and oxygen diffuse into cells. Carbon dioxide and waste substances diffuse out.
Osmosis is the movement of water molecules from a dilute solution into a more
concentrated solution through a partially permeable membrane.
Water passes into plant cells by osmosis. A plant cell that is full of water is turgid. If plant
cells are placed in a strong solution, water passes out by osmosis. As a vacuole shrinks
the cell membrane eventually peels away from the cell wall – the cell is plasmolysed.
If animal cells are put into a weak solution they take in water and burst.
Particles can be taken into a cell against a concentration gradient. This process needs
energy so is called active transport.
Task
Hints
Plan an investigation into the effects of sugar
solution on potato cells.
You could find out how different concentration of
solutions affect the mass or length of potato
chips.
You must follow the lab report format given.
Before carrying out your plan, check with your
teacher that it is safe to do so.
You could also measure the flexibility of the
chips.
You could find out the effect of temperature on
turgidity.
Read though pages 16 – 25 in your textbook to
help with planning your investigation and the
linked content.
Self Reflection:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Teacher’s comments:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Student Name:
Title:
Class:
Date:
Part 1 : Introduction
Aim: you should give the aim of the investigation
Hypothesis: you need to write the hypothesis and prediction of the investigation. The hypothesis needs to be
very clear, giving an exact and complete description of what might happen (and why). The prediction is
written like: If …then…
Theoretical Background:
Give a general background to the study, you may take it from the Instruction sheet.
Give any formula related to the investigation
Independent Variable is the one that you alter (change) throughout your experiment. For an example, if you
investigate the effect of force on the acceleration of an object, then the different forces that you use are the
independent variable
Dependent Variable is the variable that you measure. Using the previous example, the dependent variable
would be the acceleration of the object.
Controlled variables are the ones that you try to keep constant throughout your experiment so that they
don’t affect your experiment. If investigating the effect of force on the acceleration of an object, the
controlled variables would be the mass of the object, the frictional force (by using the same surface), etc.
Equipment: give a list of all the equipment used in the experiment. Give the size of beakers/measuring
cylinders, etc, used, give the names of any chemicals that are used in the experiment.
You can use a diagram (picture) to show the experimental set up if you find it necessary.
Procedure:
- Now you should describe the method. It should be written in past tense (i.e. not written as a guide on how
to carry out the experiment again, but rather, how you did it). The steps in the experiment are either selfevident or explained
- In this part you should explain the different variables. Write how the independent variable was varied,
using the previous example, you should write how can you change the used force (by adding different masses
for example)
- Write how changes of the dependent variable were monitored. You should write how you got your
results.
- Write how the controlled variables were controlled. Using the previous example, you write that you made
sure that the same object (trolley) was used and that you carried the experiment on the same plane.
- Write how you made sure that the sufficient relevant data was recorded. Describe the method for data
collection, i.e. if you had several trials, if you used controls, methods of measurements, if your calculations
are correct, etc.
Part 2 : Data Collection and Data Processing
Raw Data:
 Record all your raw data in tables. The tables should be numbered and have captions in which you
briefly describe the contents of the tables and how you recorded the results. Titles and units should be
given in the headings of the tables.
 Underneath the table you can write or briefly describe the results. You can describe the main trends
and account for any anomalous result. You don’t have to discuss the significance of the results to the
aim of the investigation.
Data Processing:

The data should be processed (calculated) correctly and presented in tables (as above) and graphs. If
you use graphs, they should have a caption in which you describe the contents of the graph. The axes
of the graphs have to be labelled with units and the points have to be plotted correctly. Make sure that
you use the correct type of graphs. If both variables are continuous, use a point graph.
Part 3 : Conclusion and Evaluation
Conclusion


In the conclusion you should discuss the results you obtained in relation with your hypothesis.
Write a conclusion based on an interpretation of the gathered results.
Compare your results with literature values if possible.
Evaluation



In the evaluation you should evaluate the method used. Write about the main weakness of the
method used and the weakness in the method of manipulation of data.
Write about the source of error, but don’t include personal mistakes.
Suggest real improvements (that can be carried out in the school lab) to the investigation.
Resource: http://goto.glocalnet.net/ibweb/homepagelink.htm