Year 10 Biology
Feedback for lab report (10Hope)– Effect of temperature on DNA extraction from a banana
Criteria B: Inquiring and designing
i.
ii.
iii.
iv.
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Explain a problem or question to be tested by a scientific investigation
Very little background information included – why is this experiment important in the real
world? How could people use your results?
Why should we even bother doing this experiment? Relate to its importance and what we can
do with the results.
State you title and aim in detail – what temperatures are you using, how will you change these,
what are you extracting DNA from, how will you do that.
Formulate a testable hypothesis and explain it using scientific reasoning
Many said DNA being extracted – but didn’t mention from what in their aim/title/hypothesis
More correct scientific reasoning in the hypothesis – WHY do you think you will get the results
you have predicted?
Make sure you site everything and include footnotes to back up where you got your
information from.
You need to convey that you actually understand this – do not just copy and paste something
and change it about a bit – explain in clear English.
Explain how to manipulate the variables, and explain how data will be collected
Variables more detail – amounts, sizes, units
How will you control the control variables?
How will you manipulate the independent variable?
How will you measure the dependent variable?
How will you collect data?
Put this into a table
You need more than just one control variable
Describe WHY you need to control/manipulate/measure that variable and how you will do
this. How will it affect your results if you don’t? Back up with science
Design scientific investigations
Lots of you didn’t put in a risk assessment – you need to show that you can make a SAFE
method. What could be hazardous? How will you stop it from occuring? What will you do if it
occurs?
Methods must be very detailed – do not just copy my method or one given to you as you WILL
ALL HAVE THE SAME and it is not detailed enough!
All details included – don’t just put: ‘Add the ethanol’ – you need to describe in detail HOW the
ethanol needs to be added: ‘Fill a pipette with 5mL ethanol, gently squeeze this down the inside
of the test tube…’
Many unfinished methods – ALL steps must be included in detail
Quantities of equipment in equipment lists
Many of you forgot the water baths (key part of the experiment!)
Describe how the DNA is actually measured – not just ‘with a ruler’
Should be able to give this to someone and they can go and do the experiment without asking
questions
Should refer to variables
Criteria C: Processing and evaluating
i.
ii.
iii.
iv.
v.
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Present collected and transformed data
Table must be correct OR graph must be correct
Do not just copy my table/one given to you – it will be very brief and needs adjusting
All decimal points must be the same in a table: i.e. all must have 1dp, or 2dp or no dp. (you can
have 1.1, 1.5, 10.1…but not 1, 1.53, 10.104 – these need to be consistent)
Title, axes labels on graph
Line graph – with a line of best fit/curved line (not dot to dot)
Graph should either be done on computer or in pencil
Units included on axes
Table needs to be very clear what you are recording – need a title, labels, and units
To get a high mark – BOTH must be correctly presented.
Interpret data and explain results using scientific reasoning
Include data from your table – describe the results that you got
Very little scientific reasoning used to try to explain results
WHY did you get the results that you did?
Evaluate the validity of a hypothesis based on the outcome of the scientific
investigation
Must mention your hypothesis – do your results agree or disagree? Why?
Must include results from your experiment to back it up
What could your hypothesis be re-written as?
Evaluate the validity of the method
Not many mentioned variables – did this make method fair?
What weaknesses were in your method – how did this affect results?
A lot of you made this personal – I did this…he did that – it needs to be generally about your
method. What could go wrong at each step?
Put this into a table with point V.
Explain improvements or extensions to the method
Only a few included this
What could be done to improve your results
Why would that make it better?
Back up scientifically
Put into a table with point IV.
Other
Very few bibliographies/references
Very little text citation
You need to do more research – and then show me your understanding in the text – back up your
points with scientific information, and tell me where you learnt that information.
Overall presentation – not good!
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Underline or make subheadings bold
Use capital letters!
Leave spaces between each part
Make sure whole table is on one page
List method using numbers
Put variables into a table
Make sure units are on table/graph
Make sure all labels in table are on one line (words are not split over two lines)
Put risk assessment into a table
Put improvements for method into a table
Check spelling, grammar and sentence formation
Check your English makes sense!