You are asked to set up an experiment to investigate the effect of temperature on the rate of germination. You place ten soaked peas in every of three flower pots containing moist sand. One pot is placed in a refrigerator at 4°C, one is placed in a cupboard at room temperature (about18°C) and the third is placed in an incubator at 25°C. You leave them for a week, checking every day that the sand is kept moist.

   (a) How would you judge the results?

   (b) Why was the pot, at room temperature, kept in a cupboard rather than on the laboratory bench?

(a) To compare the extent of germination at every temperature you would require measuring the height of the shoots and the lengths of the roots of the seedlings from every pot. The   measurements for each temperature would then be averaged and compared. You could also count the number of leaves and lateral roots, if any.

(b) Because the seeds in the refrigerator and incubator would be in darkness, it was necessary  to keep the ones at room temperature in darkness as well; otherwise, any difference in germination may be attributed to a difference in light rather than to a dissimilarity in temperature.