Name:​
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Date:
Gummy Worm Meiosis
Objectives:
●​ The student will understand meiosis occurs only in the sex cells(gametes) and involves two
divisions, as compared to one division in mitosis (body cells).
●​ The student will know the stages of meiosis and understand what is occurring in each step.
●​ The student will understand the purpose of chromosomes in the process of meiosis.
●​ The student will understand that meiosis is essential for the process of reproduction.
Materials:
Materials
Gummy worms
Toothpicks
Paper Towel
Grey Yarn - various sizes
White Yarn
Scissors
Meiosis Component
Procedure:
Interphase 1:
●​ Obtain 4 gummy worms and place them on a clean paper towel- the cell.
●​ Note- each gummy worm will count as 1 chromatid
●​ Replicate the gummy worms to create a total of 8 chromatids.
●​ Use the largest Grey Yarn to create a nuclear membrane around the sister chromatids.
Meiosis 1
Prophase 1:
●​ Create 4 pairs of sister chromatids with the 8 gummy worms. Note-make sure you put the
matching colors together. Use the toothpick to hold the sister chromatids together to represent
the centromere, the two pairs of sister
chromatids represent a tetrad/ set of
homologous chromosomes.
●​ Cut off a 2 cm piece from the bottom of one
chromatid from each pair and switch them to
indicate crossing over. (You will have 2 sets, not just one like the picture above).
●​ Take away the Grey Yarn as the nuclear membrane has disappeared. (Set aside)
●​ Use the White Yarn to create spindle fibers
Metaphase 1:
●​ Line up the Homologous Chromosomes down the middle of the cell (paper towel)
●​ Attach the spindle fibers appropriately to the centromere of the sister chromatids
●​ Move the centrioles to the appropriate location within the cell - think back to the Mitosis Lab
for placement.
Anaphase 1:
●​ Move the spindle fibers appropriately to represent the pulling apart of the homologous
chromosomes.
●​ Take each of the homologous chromosomes and move them to opposite ends of the cell.
Telophase 1
●​ The homologous chromosomes should now be at opposite ends of the cell.
●​ Use the medium size pieces of grey yarn to create two new nuclei.
●​ The spindle fibers should no longer be present. (Set aside)
Cytokinesis
●​ As the cell starts to divide into two cells it starts to form a cleavage furrow. Carefully pull apart
the “cell” partway to represent this.
●​ Eventually, completely separate/cut the paper towel “cell” all the way across to show that
cytokinesis has occurred.
●​ You should have two diploid cells.
Meiosis 2
Prophase 2:
●​ You should now have 2 separate “cells” with two pairs of sister chromatids in each.
●​ Ensure your nuclear envelope and spindle fibers are present and in the appropriate location.
Metaphase 2:
●​ Line the sister chromatids up along the middle of each cell
●​ Attach the spindle fibers to the centromere.
●​ Move the centrioles to the appropriate location within the cell.
Anaphase 2:
●​ Move the spindle fibers appropriately to represent the pulling apart of the sister chromatids.
●​ Split the sister chromatids apart and move them to opposite ends of the cells to complete
independent assortment.
●​ Ensure your centrioles are in the appropriate location within each cell.
Telophase 2:
●​ The chromatids should now be at opposite ends of each cell. (Each should have 2 single
stranded chromosomes – gummy worms!)
●​ Spindle fibers should no longer be present (Set aside)
●​ Use the smallest grey yarn pieces to create four new nuclei around the chromosomes.
Cytokinesis:
●​ Split the paper towel down the middle to represent cytokinesis in each cell to create
4 individual cells (gametes) with a nucleus and two chromatids.
Name:​
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Period:​
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​
​
Date:
Gummy Worm Meiosis Lab
Assessment Questions:
1.​ What is the purpose of Meiosis?
2.​ What are homologous chromosomes?
3.​ Which stage are there homologous chromosomes lined up down the middle of the cell?
4.​ Which stage are there sister chromatids lined up down the middle of the cell?
5.​ When does independent assortment occur?
6.​ Describe the result of independent assortment.
7.​ What does it mean to be diploid? Give an example of a diploid cell
8.​ What does it mean to be haploid? Give an example of a haploid cell
9.​ At the end of Meiosis I
a.​ How many cells are there?
b.​ Are they haploid or diploid?
10.​At the end of Meiosis II
a.​ How many cells are there?
b.​ Are they haploid or diploid?
11.​Drawing Conclusions: Look at your four gametes. How does meiosis lead to increased genetic
variation? (consider crossing over)
12.​Predicting: How would the gametes be affected if a pair of chromatids failed to separate in the
second meiotic division?
13.​Explain: Meiosis is often described as a reduction division process. Explain how this is an accurate
description for the process.
14.​Exploring: What is meant by the statement: “Meiosis results in gene segregation”?
Name of Phase
Description
Homologous chromosomes pair up
Spindle fibers move homologous chromosomes to opposite sides
Nuclear membrane reforms, cytoplasm divides, 4 daughter cells formed
Chromosomes line up along equator, not in homologous pairs
Crossing-over occurs
Chromatids separate
Sister chromatids line up along the equator
Cytoplasm divides, 2 daughter cells are formed