Meiosis: How Does the Process of Meiosis Reduce the Number of Chromosomes in Reproductive Cells?

Contributor
or Sampson, Patric Enderle, Leeanne Gleim, Jonathon Grooms, Melanie Hester, Sherry Southerland, and Kristin Wilson
Type Category
Instructional Materials
Types
Lesson/Lesson Plan
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

This lab activity introduces students to the process of meiosis at the chromosomal level. The guiding question for the investigation is: How does the process of meiosis reduce the number of chromosomes in reproductive cells? Students develop an explanatory model based on their knowledge of mitosis and how cells divide. Students are provided with pictures showing various stages of meiosis. Students sequence the pictures and provide a description of what they think may be going on during each stage. The book provides a link (www.nsta.org/publications/press/extras/argument.aspx) to download images of meiosis (sequencing activity). Students use pop bead chromosomes (provided by the teacher) to create a valid model that explains : what happens to the chromosomes inside a cell as it goes through meiosis, why reproductive cells have half the number of chromosomes of the individuals who produce them, and why there are no pairs of chromosomes in reproductive cells. When students have finished the model, and after they have collected and analyzed the data, they develop an initial argument. They prepare a whiteboard presentation that includes the guiding question, claim, evidence, and justification of evidence and present it to the whole-class using a round-robin format. After collecting feedback, students return to their original small groups for editing and revising before writing a final report. Each lab ends with a list of checkout questions. The book includes an option to extend the lesson by asking students to complete a double-blind peer review of the argument using a rubric provided in the appendix. To provide additional support, four appendixes are included: standards alignment matrixes, options for implementing argument-driven inquiry lab investigations, investigation proposal options, and peer-review guide and instructor scoring rubric. A detailed step-by-step guide that explains the argument-driven inquiry is included for teachers not familiar with the model.

Intended Audience

Educator and learner
Educational Level
  • Grade 12
  • Grade 11
  • Grade 10
  • Grade 9
Language
English
Access Restrictions

Available for purchase - The right to view, keep, and/or download material upon payment of a one-time fee.

Performance Expectations

HS-LS3-1 Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring.

Clarification Statement: none

Assessment Boundary: Assessment does not include the phases of meiosis or the biochemical mechanism of specific steps in the process.

This resource appears to be designed to build towards this performance expectation, though the resource developer has not explicitly stated so.

Comments about Including the Performance Expectation
Teacher’s notes include a brief summary of the content needed for this activity. Teachers should not provide a lesson on meiosis prior to this lab. If students are encouraged to focus on the “Introduction,” “Your Task,” and the “Getting Started,” sections of the student pages, they develop a better conceptual understanding of the goal of meiosis rather than memorizing stages. Prior knowledge of mitosis supports students in developing their model of meiosis. During the explicit and reflective discussion, teacher needs to support students in making connections among DNA replication, chromosome structure and function, and how meiosis prevents chromosome overload. Pop bead kits for making chromosomes can be purchased from Carolina Biological (http://www.carolina.com/), Flinn Scientific (http://www.flinnsci.com/), or Ward’s Science (https://www.wardsci.com/). Each group will need at least eight pop bead chromosomes (two long chromosomes using red beads, two long chromosomes using yellow beads, two short chromosomes using blue beads, and two short chromosomes using pink beads). This combination allows students to combine the chromosomes that are the same length and color to make four sister chromatids. If students are unfamiliar with the argumentation strategy and scientific writing, teachers can use scaffolding to model and provide examples at each step of the lesson. It will be helpful to remind students to return each pop bead chromosome to its original form before leaving the classroom.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Teachers can provide a review of DNA using a HHMI's Film (The Double Helix) or Youtube videos. Students are engaged in the practice when they use their knowledge of DNA and its role in mitosis to develop a model that explains the process of meiosis using pop bead chromosomes. During the closing discussion, teachers should encourage students to reflect on the strengths, weaknesses, and revisions of their investigation. Teachers need to provide instruction and model how to provide critical and positive feedback during the argumentation stage of the lesson. To determine level of understanding, teacher can ask students to create an analogy comparing mitosis and meiosis to everyday phenomena or objects.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
Students use their knowledge of basic cell structure and function, how cells divide during the process of mitosis, and the relationship between chromosome structure and function in gametes to create an explanatory model of meiosis. Teachers could ask students to reflect on the probability of survival of a cell that does not have a reduced chromosome number. Meiosis is an important source of variation in offspring. Through questing and discussion, teachers should support students to develop an understanding of how crossing over during meiosis leads to genetic variation. Teachers can extend the lesson by asking students to use beads to create a model of crossing over.

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
Students identify the underlying cause of an observed pattern as they sequence the stages that are observed during meiosis. Students need to determine if their model is valid by comparing it with the images of cells going through meiosis and what they know about mitosis. Teachers should provide each group with pictures of cells going through meiosis for the sequencing activity. Meiosis images can be printed from a PowerPoint file at (http://www.nsta.org/publications/press/extras/argument.aspx). Following the chromosomes during meiosis provides a way to understand certain patterns of inheritance. Teachers can provide students with pictures of cells going through mitosis to review prior knowledge of cell division.

Resource Quality

  • Alignment to the Dimensions of the NGSS: This lab engages students in multiple practices. Students are asked a guiding question and students use prior knowledge and collected data from the activity to develop an explanatory model on meiosis.

  • Instructional Supports: The Teacher Notes for each investigation include information about the purpose of the lab, background and new content, the time needed to implement each stage of the lab, the materials needed, and hints for implementation. The book provides suggestions on how to encourage students to reflect on the strengths and weaknesses of their investigations and ways to improve future investigations. To provide additional support, four appendixes are included: standards alignment matrixes, options for implementing argument-driven inquiry lab investigations, investigation proposal options, and peer-review guide and instructor’s scoring rubric. A detailed step-by-step guide that explains the argument-driven inquiry is included for teachers not familiar with the model. The book provides a link (www.nsta.org/publications/press/extras) to download images of meiosis (sequencing activity).

  • Monitoring Student Progress: Each lab investigation includes a set of checkout questions. The questions target the key ideas, crosscutting concepts, and the nature of science concepts for each of the 27 lab activities. Teachers must act as facilitators and resources for the students. They should rotate among the groups asking probing questions and listen to students’ questions and answers. Students should be encouraged to answer their own questions and should be allowed to fail in order to develop new solutions. Teachers can use the students’ responses, whiteboard presentations, and scientific report to determine if students learned what they needed during the lab or if re-teaching is required.

  • Quality of Technological Interactivity: This lab does not contain a technology component.