AP Biology
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College Board exam questionsENGLISH-LANGUAGE BIOLOGY PRACTICE
Interpret an oxygen-exchange graph, design a fair test and build an answer from experimental evidence.
01 · READ THE CONTEXT
Choose the term that fits each description.
02 · READ THE GRAPH AND TABLE
An algal culture is exposed to different light intensities at two carbon dioxide levels. Compare its net oxygen exchange. This dataset was created for practice.
Net O₂ exchange (µmol/min)
| Light intensity (µmol photons/m²/s) | Lower CO₂ | Higher CO₂ |
|---|
Negative values indicate net oxygen uptake.
03 · CHOOSE WHAT TO CHANGE AND MEASURE
A student investigates how pH affects catalase. Catalase helps break down hydrogen peroxide, releasing oxygen. The student compares the oxygen volume collected during the first 60 seconds at each pH.
04 · CONNECT AN OBSERVATION TO A CLAIM
An intact model membrane bag initially contains starch solution without iodine. The liquid outside contains iodine indicator and starts without starch. The indicator turns blue-black when it contacts starch.
| Sample | Start | End |
|---|---|---|
| Inside the bag | Cloudy white | Blue-black |
| Outside the bag | Amber | Amber |
The observations support iodine reaching the starch inside the bag. Only the liquid inside turned blue-black. Because iodine was initially outside and this colour forms when iodine contacts starch, the result supports iodine crossing into the bag.
05 · OFFICIAL WEBSITES
The activities above are original practice. Follow the official links for programme information and published materials.
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Cambridge course pageRead the subject overview and find the subject briefs.
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IBO exam archiveOnion root-tip micrograph by Doc. RNDr. Josef Reischig, CSc., cropped and resized. Original photograph · CC BY-SA 3.0.