Meiosis in Action! Lab Sheet
Name: _______________________
Period: ______________________
Objective: To demonstrate your understanding of the process of meiosis, crossover, and implications of these
events for future generations.
Pre-Lab:
1.
Observe the chromosomes at your lab stations.
a. How many replicated chromosomes (sister chromatids) are there?
b. If these are all from one organism; what is the diploid number of that organism (total)?
c. What is the haploid number of that organism (pairs)?
Part I Interphase:
a. Draw the outline of a cell on the lab bench with chalk.
b. Prepare the cell for meiosis by placing the replicated chromosomes in the cell.
DRAW your Chromosomes here for your DIPLOID cell:
1.
Interphase I: DNA replicates, centrioles form
a. Verify your drawing with Mrs. Moberly_______
Part II Begin Meiosis:
1.
Prophase I
a. Arrange your chromosomes in the cell.
b. Draw prophase I.
c. What happens during prophase I?
d. Verify with Mrs. Moberly _______
2. Metaphase I
a. Arrange your chromosomes in the cell.
b. Draw metaphase I.
c. What happens during metaphase I?
d. Verify with Mrs. Moberly _______
3. Anaphase I
a. Arrange your chromosomes in the cell.
b. Draw anaphase I.
c. What happens during anaphase I?
d. Verify with Mrs. Moberly _______
4. Telophase I
a. Arrange your chromosomes in the cell.
b. Draw telophase I.
c. What happens during telophase I?
d. Verify with Mrs. Moberly _______
5. Prophase II
a. Arrange your chromosomes in the cell.
b. Draw prophase II.
c. What happens during prophase II?
d. Verify with Mrs. Moberly _______
6. Metaphase II
a. Arrange your chromosomes in the cell.
b. Draw metaphase II.
c. What happens during metaphase II?
d. Verify with Mrs. Moberly _______
7. Anaphase II
a. Arrange your chromosomes in the cell.
b. Draw anaphase II.
c. What happens during anaphase II?
d. Verify with Mrs. Moberly _______
8. Telophase II
a. Arrange your chromosomes in the cell.
b. Draw telophase II.
c. What happens during telophase II?
d. Verify with Mrs. Moberly _______
Part III Crossover:
Sometimes even MORE variation can happen in meiosis! Rewind your chromosomes so they are back in prophase I:
Verify with Mrs. Moberly ______
Sometimes the homologous chromosomes SWITCH segments of their DNA with one another…
Simulate crossover by switching a segment of one chromosome with the other. The trade is always even!
Verify with Mrs. Moberly _______
Now go through the phases of meiosis again and draw the resulting gametes:
Verify with Mrs. Moberly _______
Part IV Analysis:
1. State whether cells are diploid or haploid in the following phases:
a. Prophase I:
b. Telophase I:
c. Telophase II:
2. How does the process of meiosis lead to genetic variation in offspring? (Why are you different from your siblings?)
3.
Explain how crossover can lead to even MORE variation in offspring. Describe how this affects how an offspring will turn
out compared to their parents.
4.
Describe in detail how meiosis is a process that is necessary for life. Use your experiences in class to support your answer.