Genetic Cross Investigation
Punnett Square


Follow the instructions below. Printout the results sheets, complete the Punnett Squares and results and give your completed assignment to your instructor.

  1. print out this sheet of partental phenotypes and genotypes
  2. the last four numbers of your social secturity number are the numbers of the crosses you must investigate
  3. mark each number (4 all together) on the parent sheet and put your name and section at the top of the page
  4. if there are any duplicate numbers, choose a replacement cross
  5. print out the results sheet(s)
  6. use these results sheets to perform the Punnett Square on the each of the various genetic crosses you have been assigned
  7. work out all the possible haploid gametes that each parent can produce by meiosis
  8. write each gamete genotype along one side of the Punnett Square (male and female separately)
  9. fill in the internal boxes of the square with the genotypes of the offsprings that would be produced
  10. from the Punnett Square results, determine the range of phenotypes obtained, put each phenotype into one of the boxes at the bottom of the page
  11. count the number of offspring that have that particular phenotype
  12. record that number
  13. put your name and section number at the top of the page and give your results to your instructor as requested

Science at a Distance
© 2004, Professor John Blamire