Student Exploration: Meiosis
Vocabulary: anaphase, chromosome, crossover, cytokinesis, diploid, DNA, dominant, gamete,
genotype, germ cell, haploid, homologous chromosomes, interphase, meiosis, metaphase,
mitosis, ovu
...
Student Exploration: Meiosis
Vocabulary: anaphase, chromosome, crossover, cytokinesis, diploid, DNA, dominant, gamete,
genotype, germ cell, haploid, homologous chromosomes, interphase, meiosis, metaphase,
mitosis, ovum, phenotype, prophase, recessive, sister chromatid, sperm cell, telophase, zygote
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. During mitosis, a single cell divides to produce two daughter cells. What must happen in the
original cell so that each of the daughter cells has a complete set of chromosomes?
A cell must grow
2. During sexual reproduction, two sex cells fuse to create a fertilized cell with a complete set
of chromosomes. What must be true about the number of chromosomes in each sex cell?
Haploid cells
only have one set of chromosomes - half the number of chromosomes as the parent cell.
Gizmo Warm-up
Meiosis is a type of cell division that results in four daughter
cells with half as many chromosomes as the parent cell.
These daughter cells mature into gametes, or sex cells. In
the Meiosis Gizmo, you will learn the steps in meiosis and
experiment to produce customized sex cells and offspring.
On the STEPS tab, click Male. You are looking at a germ
cell, or a cell that will undergo meiosis to become gametes.
1. Read the description of interphase at the bottom of the Gizmo. What happens to the cell at
the beginning of interphase? ___ cells grow synthesize mRNA and proteins required for
DNA synthesis
2. Click on the DNA in the nucleus of the cell. Describe what happens.
DNA is copied and the dell grows some more
3. Why is it necessary for the cell to grow and duplicate its DNA before the start of meiosis?
because existing cells divide to produce new cells. ... So the DNA needs to be copied
before cell division so that each new cell receives a full set of instructions.
Activity A:
Steps in meiosis
Get the Gizmo ready:
● Make sure the STEPS tab is selected.
● If necessary, choose the Male cell. Click on the
DNA to copy it to proceed to prophase I.
Introduction: Unlike mitosis, which produces two identical daughter cells from one parent cell,
meiosis creates four unique daughter cells with half the amount of DNA as the parent cell.
Question: How does meiosis create four daughter cells from one parent cell?
1. Observe: (Prophase I) Click on the nucleus to break it down then click on the DNA to
condense it into chromosomes. Drag the centrosomes to the top and bottom of the cell.
A. How many chromosomes does this cell have? 4
Each chromosome consists of a pair of sister
chromatids, two identical strands of DNA that
formed when DNA replicated during interphase.
B. On the image to the right, draw two lines connecting
the pairs of homologous chromosomes
(chromosomes of similar size with a matching set of
genes).
In the Gizmo, drag the homologous chromosomes
together. Click Continue.
2. Observe: (Metaphase I and Anaphase I) - Drag the groups of homologous chromosomes to
the metaphase plate, then drag spindle fibers from each of the centrosomes to the
chromosomes. Click the centrosome to pull the chromosomes apart.
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