How to write an IB Biology Lab Report - Design, by Alex Lee on YouTube. 7 min 50 s.
- Video length
- 7 min 50 s
- Time to do it
- 30 minutes
- Difficulty
- Medium
- Steps
- 10
What you need
Steps
Write your research question as one sentence that names both variables, such as: how does light intensity affect the rate of photosynthesis in Elodea?
Add a short background paragraph on the biology behind the question. Explain what the variables mean and cite a textbook or trusted source.
State your hypothesis in one or two sentences. Predict the direction of the effect and give the biological reason from your background research.
Describe the independent variable: the values you will use (at least five) and how you will set and measure each one.
Describe the dependent variable and exactly how you will measure it, including the instrument, the units and the precision, for example nearest 0.1 cm.
List each controlled variable and the practical way you keep it constant, such as a water bath at 25 C, the same volume of solution and the same species of leaf.
Write the method as numbered steps another student could follow. Give volumes, concentrations, distances, times and how many repeats you will run.
List the apparatus and materials with sizes and quantities, for example a 250 cm3 beaker, a 5 cm length of Elodea and 100 cm3 of 1 percent sodium hydrogen carbonate.
Add a safety line covering the real risks: goggles for chemicals, care with glassware and hot water, and how you will dispose of waste.
Plan a raw data table with a clear title, units in the column headings and a row for every repeat before you start collecting data.
Tips and common mistakes
Keep the variable names identical in the question, hypothesis and method so the design reads as one connected piece.
Say how you will measure, not just what: "measure to the nearest mm with a ruler" beats "measure the length".
Pick at least five values of the independent variable so you can plot a meaningful graph later.
Avoid vague words like "some" or "a while". Real numbers make the method repeatable.
Questions
What goes in the Design section of an IB Biology report?
The research question, background, hypothesis, variables, method, apparatus and safety. Together they should let another student repeat your experiment.
How many variables do I need to list?
One independent variable, one dependent variable, and every controlled variable you can realistically keep constant, each with the way you control it.
Do I have to include a hypothesis?
Yes. State the expected direction of the effect and give a biological reason for it, rather than just guessing.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
