The Punnett Square shows only the probability of what might occur and not the actual results. Probability is the chance of somthing occurring. If one wants to flip a coin 100 times, since there are 2 sides to the coin, he would expect 50 heads and 50 tails. If he flips the coin 100 times, he may actually get 60 heads and 40 tails.
Prediction is one thing, and actually getting the predicted results is another.
The Punnett square only shows the chances of what might occur each time the event is under taken. This represents 2 heterozygous parents Gg x Gg . 2. One student in the group will be incharge of the male bag, the second student will be incharge of the female bag, and the third student will be the data keeper. At the same time, each of the students controlling the bags of gametes, will reach into their bag and pull out one of the beads. The third student will marke the resulting combination in the data sheet at the bottom of the page.