Instructions

Questions usually give the symbols to be used, in which case always use the ones provided. Choose a single letter to represent each characteristic. Choose the first letter of one of the contrasting features. If possible, choose the letter in which the higher and lower case forms differ in shape as well as size. If possible, choose the letter in which the higher and lower case forms differ in shape as well as size. Let the higher case letter represent the dominant feature and the lower case letter the recessive one. Never use two different letters where one character is dominant. Represent the parents with the appropriate pairs of letters. Label them clearly as 'parents' and state their phenotypes. State the gametes produced by each parent. Label them clearly, and encircle them. Use a type of chequerboard or matrix, called a Punnett square, to show the results of the random crossing of the gametes. Label male and female gametes even though this may not affect the results.