Before Strategy/Engage: 50 minutes (Day 1)
1. The teacher should give each student a copy of the Pre-/Post-Test Meiosis (see attached document). The teacher should give students approximately ten to fifteen minutes to complete the pre-test. The teacher should stress to students that the purpose of the pre-test is to demonstrate the student’s background knowledge about the concept of meiosis.
2. After students complete the pretest, the teacher should check students’ answers to determine their current knowledge base of the concepts using the Pre-/Post-Test Meiosis with Answers (see attached document). Alternatively, the teacher could allow students to check their own paper or check a partner’s paper.
3. The teacher should display the following questions on the board or chart paper to lead an interactive class discussion. (See attached Questions to Ponder document.)
Possible Answer: Chromosomes vary during meiosis due to crossing over and possible mutations which cause variations in genetic make-up.
Possible Answer: The egg, which comes from the mother, contains half of yours and your siblings’ chromosomes (genes). The sperm, which comes from your father, contains the other half of your and your siblings’ chromosomes (genes). The egg and sperm are combined during fertilization and make up your diploid chromosome number (full set of chromosomes).
Possible Answer: One copy is contributed by each parent. After meiosis, each sex cell contains only one copy so that during fertilization the zygote does not contain more than 46 chromosomes (the normal diploid number for humans).
4. The teacher should give each student a copy of “A Survey of My Traits” (see attached document). The student should check off applicable traits. Next, the teacher should allow students to discuss their responses with a partner and lead a class discussion about the most common traits among the class members.
During Strategy/Explore & Explain: 100 minutes (Days 2 and 3)
For the next portion of the lesson, the teacher should divide students into eight collaborative groups.
1. The teacher should give each student a copy of the Student Lab Sheet I Meiosis and the Answer Sheet Student (see attached documents). This lab sheet will provide detailed instructions on setting up the cell and genome, as well as modeling the stages of interphase, prophase I, metaphase I, anaphase I, telophase I, prophase II, metaphase II, anaphase II, and telophase II. The students will answer questions included on the lab sheet on their answer document.
2. After students have completed the first lab activity, the teacher should give each student a copy of the Student Lab Sheet II Gamete (see attached document). The students will record their answers on the same Answer Student Sheet that was previously distributed. This lab sheet provides detailed instructions on modeling the formation of egg and sperm cells.
After Strategy/Explain & Elaborate: 50 minutes
1. After all groups have completed the lab activities, the teacher should lead a class discussion among all of the groups to compare each group’s observations and data collected during the lab activities.
Note: If the teacher identifies that students need additional review before the summative assessment, the teacher may show students the Modeling Meiosis presentation to review the concepts demonstrated during the lab activities (see attached PowerPoint presentation).
2. The teacher should give the students the Pre-/Post-Test – Meiosis, that students completed as a pre-test at the beginning of the lesson. The teacher should explain to students that this post-test will allow students to demonstrate the knowledge they acquired during the lab activities.