Campbell Biology (11th Edition)

Published by Pearson
ISBN 10: 0-13409-341-0
ISBN 13: 978-0-13409-341-3

Chapter 13 - Test Your Understanding - Level 3 - Synthesis/Evaluation - Page 268: 9

Answer

The crossing over shown in question 6 shows one crossing over event between two non-sister chromatids. Thus, the gametes would be two unchanged from the parental types (freckles-black hair; no freckles-blond hair) plus two recombined versions (freckles-blond hair; no freckles-black hair). These are all of the four possible combinations for these two genes with two alleles per gene.

Work Step by Step

Look closely at the diagram in question 6: you can see that two non-sisters from the long chromosome have crossed over while the other two non-sisters have not. This will lead to the described four combinations in the four gametes resulting from this meiosis.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.