Leaf Disk Lab

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Observation

Watch photosynthesis happen

0.0 min · 0 / 10

Ten disks are at the bottom of the beaker.

Virtual lab

Photosynthesis in a beaker

Watch ten spinach disks. Oxygen made by the leaf helps each disk float.

Model details

This is an illustrative teaching model. Real leaves vary. The times are examples for comparing conditions, not predictions of real lab times.

Photosynthesis makes oxygen. Respiration uses oxygen in light and dark. A disk rises after enough oxygen builds up in its air spaces.

Green light can support photosynthesis, but it is less effective here. A green leaf reflects much of the green light. More heat does not always help. At 45 °C, the enzymes stop working in this model.

About this activity

Measure photosynthesis with floating spinach leaf disks. Compare light color, brightness, temperature and bicarbonate, then explain your evidence.

Related lessons

Instructions

Remove the air, add bicarbonate solution, and turn on the lamp. Oxygen made by the leaf helps the disks float.

Predict first. Change one condition at a time. Compare the minutes until 5 of 10 disks float.

Each trial lasts 45 simulated min. Choose 5×, 15×, or 60× playback. At the default 15×, a full trial takes 3 real minutes. Pause and Skip to end change your wait, not your results.

This is an illustrative teaching model. Real leaves vary. The times are examples for comparing conditions, not predictions of real lab times.

Record your observations on your worksheet. Trial data stays on this page until you reload, reset an investigation, or change language. Nothing is saved or sent.