Module 6
1. Module 6
1.36. Lesson 8
Module 6—Mendelian Genetics: The Transmission of Traits to the Next Generation
Lesson 8—Polygenetic Traits
Get Focused
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The top of a chicken’s head has a fleshy growth known as a comb. There are four possible phenotypes for chicken combs: rose, pea, walnut, and single. You might suspect multiple alleles were responsible for this trait. However, a walnut chicken can be crossed with another walnut chicken and their offspring can display all four of the possible phenotypes. These results would not be possible with any amount of alleles if this trait were controlled by a single gene. This type of inheritance is only possible if more than one gene is acting to affect the same trait.
In this lesson, you will study traits that are controlled by many genes. You will recognize inheritance patterns that show gradual changes in phenotypes, and you will understand that the expression of one gene can turn the expression of another gene on or off.
In this lesson, the following focusing question will be examined:
- How might multiple genes combine to form a single trait?
Module 6: Lesson 8 Assignment
Your teacher-marked Module 6: Lesson 8 Assignment requires you to submit a response to questions on breeding taller corn.
Download a copy of the Module 6: Lesson 8 Assignment to your computer now. You will receive further instructions on how to complete this assignment later in the lesson.
Continue to add vocabulary, with supporting examples where necessary, to your flash cards.
You must decide what to do with the questions that are not marked by the teacher.
Remember that these questions provide you with the practice and feedback that you need to successfully complete this course. You should record the answers to all of the questions and place those answers in your course folder.
You also have the option of trying additional questions from the textbook for further practice. Consult with your teacher for the answers to these questions. The Key will also provide you with many Diploma Exam-style multiple-choice, numerical-response, and written-response questions that will be an excellent review of the module. Practising your responses to these types of questions is good preparation for the Diploma Exam.