7.+Genetics+of+Organisms+(plants)

toc =Introduction= =Procedures= =Mr. B's things=

Overview
In this laboratory, students will use living organisms to do genetic crosses. They will learn how to collect and manipulate the organisms, collect data from F1 and F2 generations, and analyze the results from a monohybrid, dihybrid, or sex-linked cross. The procedures that follow apply to fruit flies; teachers may substitute other procedures using different organisms.

Objectives
Before doing this laboratory, students should understand chi-square analysis of data and the life cycle of diploid organisms useful in genetics studies. After doing this laboratory, students should be able to investigate the independent assortment of two genes and determine whether the two genes are autosomal or sex-linked using a multi-generation experiment and analyze the data from their genetic crosses using chi-square analysis techniques.

Addressing Student Misunderstandings

 * Students may not understand the inheritance pattern associated with sex-linked traits. Be sure that students understand the genetic determination of gender.
 * The instructor should also explain the difference between linkage and sex linked. Last, be sure that the students have a clear understanding of why sex-linked traits are most often observed in males. (This cannot be done with plants!)
 * Verify that the students have a thorough understanding of the mode of inheritance-for each trait.
 * Explain Mendel’s Law of Independent Assortment. Students will need a clear understanding of this law to understand the rationale behind dihybrid crosses. Be sure that they understand that alleles for different genes are inherited independently of one another.
 * Chi-square analysis is often very confusing for students. Explain that the information collected from their experiments only contributes to the existing data. In science, we can never say that a hypothesis has been proven to be 100 percent accurate. The instructor should perform sample problems to be sure that the students have a clear understanding of chi-square analysis. Verify the degrees of freedom (df) value for each cross and explain all aspects of the chi-square table (p, critical value, etc).
 * Be sure that the students understand what it means to reject or accept a null hypothesis.

=Detailed Progress= =Photos= Students can post their photos on this page. And not on this page. (Please.)