DIRECTIONS FOR MEIOSIS ACTIVITY
In the First Circle "A"
Cut a piece of yarn this long _________(1/2 inch) from each of the four colors you are given.
Take one piece from each color and unravel it. You should now have four stands of each color.
Tape one strand from each color in the circle.
This represents Interphase, when the chromosomes are not visible.
The red/pink represent the maternal DNA and the blue/ light blue represents the paternal DNA
In the Second Circle "B"
Using the left over unraveled yarn, use two more pieces of each color.
You should have eight pieces of unraveled yarn, two of each color.
Tape them in your circle.
This represents Late Interphase.
In Circle #1
Cut two pieces from each color this long _______ ½ inch you should have eight pieces of yarn.
DO NOT UNRAVEL THEM!
Match lt. blue with lt. blue, red with red etc.
Lay them side by side, do not make them into an "X"
Tape them in your circles
This represents Early Prophase I
In Circle #2
Cut two pieces from each color this long _________ ( 1/2 inch)
Make an “X" with the matching strands; You will have one "X" of each color
Tape the X in a way that the red chromosome overlaps the blue, this is crossing over
Tape them in your circle
This represents Late Prophase I
In Circle #3
Cut two pieces from each color this long _________ ( 1/2 inch)
Make an "X" from the matching strands (just like in circle #2).
Line up the "X's" in the middle, going up and down the cell.
Tape them in your circle.
This represents Metaphase I
In Circle #4
Cut two pieces from each color this long _________ ( 1/2 inch)
Make an "X" from the matching strands.
The blue "X's" should be on the right side and the red and pink "X's" should be on the left
Tape them in your circle.
Notice the chromosomes do not separate!!
This represents Anaphase I ;(You have completed Meiosis I.)
These Cells created in Circle 4 become the separate cells in Circle(s) 5
Meiosis II
Starting at Circle #5 the cell divides just like in Mitosis, this is called Meiosis II. Remember there is no
Interphase between Meiosis I and II
Use your notes and the diagrams in your notes to help you complete cells 5 to 8
Once you have taped all the yarn in place go back and l
Label the all of the Phases of Meiosis I and II
Label the following terms:
 Chromatin
 Diploid
 Chromatids
 Homologous Chromosomes
 Chromosomes
 Crossing Over
 Sister Chromatids
 S Phase/ DNA Replication
 Haploid
 Gametes
 Tetrad
Lab Activity: Meiosis Yarn Analysis (25 pts)
Directions: Complete this worksheet based on your notes and the yarn activity…Turn this page in, it does NOT go
in your interactive notebook!!!
Phases of Meiosis:
Name of Phase
Phase Description
Homologous chromosomes pair up and form tetrad
1.
Spindle fibers move homologous chromosomes to opposite sides
2.
Nuclear membrane reforms, cytoplasm divides, 4 daughter cells formed
3.
Chromosomes line up along equator, not in homologous pairs
4.
Crossing-over occurs
5.
Sister chromatids separate
6.
Homologous pairs line up along equator
7.
Cytoplasm divides, 2 daughter cells are formed
8.
9. Define:
a. Haploid: __________________________________________________________________
b. Diploid: __________________________________________________________________
c. Homologous Chromosomes:__________________________________________________
d. Autosomes/Somatic:________________________________________________________
e. Sex Chromosomes: ________________________________________________________
10. What is the significance of meiosis in the formation of sperm and eggs?
11. By what process (meiosis or mitosis) are each of the cells formed?
a.
b.
c.
d.
e.
A stomach cell?
Meiosis or Mitosis
A liver cell?
Meiosis or Mitosis
A sperm?
Meiosis or Mitosis
A heart muscle cell?
Meiosis or Mitosis
An egg cell?
Meiosis or Mitosis
12. How many pairs of chromosomes are in each human body (somatic) cell?
13. How many pairs of chromosomes are in each egg or sperm? ____________
14. Complete the following sentences:
a. DNA replication occurs before Meiosis I occurs. DNA is replicated during ____________________
and will not be copied again.
b. At the end of meiosis I, there are
new cells with
the number of
chromosomes as the parent cell.
c. How many daughter cells are formed from each original cell? _____
d. Meiosis occurs only in
organs.
e. Meiosis is responsible for forming specialized sex cells called ___________________.
15. Do all cells of the body contain the same genetic information? ______
a. Explain.
16. What is crossing over and why does it occur?
17. If an animal has a diploid number of 36 how many chromosomes will each cell have after meiosis is
complete? ___
18. If a somatic, body, cell contains 46 chromosomes. Would this cell be considered diploid or haploid?
___________
19. How many chromosomes would a human haploid cell contain? _____
20. When an egg is fertilized, is the new cell haploid or diploid? ____________
21. A dog is 2N=78. How many chromosomes would its gametes have? ______
Name
.
Date
.Period
Directions: Use 4 shades of yarn as directed. One pair will be 2 shades of red; the other, 2 shades of blue.
A.
B
DNA
Doubles
Refer to PowerPoint
Notes
2
1
***Use heavier
Yarn from
This point on
3
4
.
5
6
7
8
(The above must contain one member of each pair of chromosomes.)