Meiosis

Transcription

Meiosis - Marcom Projects

Teacher’s Guide
Meiosis
Grades 5-9
MSTV
CREDITS
Program Production
S u n b u r s t Vi s u a l M e d i a
Te a c h e r ’s G u i d e
Te r r y G a t e s
Print Material Design
Cecile Foshee
© 2004 Sunburst Visual Media, a division of Global Video, LLC
Hawthorne, NY 10532
Approximate running time: 32 minutes
Meiosis Video Quiz
Table of
Contents
Guide Information ....................................05
Fast Facts..................................................07
Before Viewing Activities ..........................10
During Viewing Activities ..........................13
After Viewing Activities ............................15
After Viewing Quizzes ..............................18
Additional Resources ................................23
Answer Keys ............................................25
Script........................................................32
© Sunburst Visual Media, a division of Global Video, LLC
Meiosis Video Quiz
About This Guide
Guide
Information
Providing students with visual media is an excellent way to take them out of the
classroom and into the real world. Our programs offer real-world footage, dynamic graphics,
engaging dramatizations, and first-person testimonials that keep students interested and help
them visualize difficult concepts. More importantly, they reinforce critical learning objectives
shaped by state and national educational standards. However, the learning doesn’t begin and
end when the program does. You can make the learning experience even more effective by
using the materials provided in this Teacher’s Guide.
This guide is divided into the following sections:
• Fast Facts are designed to give your students a quick overview of the
information presented within the video.
• Before Viewing Activities help identify what students already know
about the subject, what they are curious about, and what they hope to learn.
• During Viewing Activities may be used during viewing to enhance
students’ understanding of the video.
• After Viewing Activities help students summarize and draw conclusions
from the information that was presented.
• After Viewing Quizzes test students’ retention of the information presented
in the program and activity sheets.
• Additional Resources are designed to help you extend the information
presented in the program into other areas of your curriculum.
• Answer Keys are provided for relevant activities or reproducible pages.
• Script content is provided in an unabridged version for future reference.
5
Meiosis Video Quiz
Program Overview
Guide
Information
Join Professor Science as he presents the basic concepts about meiosis. He covers what
meiosis is, the main parts of the cell that are involved in the process, and the different
stages of meiosis. The program is divided into two sections and at the conclusion of each
one, interesting characters present multiple-choice and true/false questions to assess your
students’ understanding of the concepts. At the conclusion
of the program, the answers are provided so students can self-check their work.
Viewing Objectives
Upon watching the Meiosis Video Quiz video/DVD, participating in the discussions,
and completing the activities given in the program guide, students will be able to:
• Define the purpose of meiosis
• List and show the stages involved in the process of meiosis
• Compare basic differences between mitosis and meiosis
• Explain why meiosis is important to the creation of offspring
• Define key vocabulary related to meiosis
• Respond to multiple choice and true/false questions
6
Meiosis Video Quiz
Meiosis Fast Facts
Fast Facts
1. Meiosis is a process of cell division.
• Most organisms need meiosis to reproduce.
• Meiosis produces special cells that allow organisms to have offspring.
• These special cells are called germ cells.
2. Every living thing is made of cells.
• Inside each cell are chromosomes that contain genetic information called genes.
• Genes determine who you are and what you look like.
3. Every organism has a certain number of chromosome pairs.
• One set of chromosomes come from the mother and one set from the father.
• Paired chromosomes are called homologous.
• Homologous chromosomes have information about the same trait such
as eye color.
4. Each cell must have one pair of each type of chromosome.
• For example, human cells must have 23 pairs of chromosomes.
• Cells with the full number of chromosomes are called diploid cells.
• Most cells in the human body are diploid.
5. Cells with only one of each type of chromosome in it are called haploid cells.
• Haploid cells have a total of 23 chromosomes, half of what a diploid cell has.
• Meiosis divides a diploid cell into four haploid cells after going through two
divisions.
• A haploid cell is a special germ cell called a gamete.
6. Gametes need to have only half of the proper number of chromosomes.
• When two human gametes fuse during fertilization, they pair up to a total
of 23 pairs or 46 total.
• Two fused germ cells create a zygote with two sets of chromosomes.
• Zygotes form when a female germ cell has been fertilized by a male germ cell.
• Offspring develop from zygotes.
7. In meiosis, one cell divides twice into four daughter cells.
• During meiosis, the chromosomes can exchange parts.
• All daughter cells differ somewhat from each other.
• Each daughter cell has only 23 chromosomes.
7
Meiosis Video Quiz
Meiosis Fast Facts
Fast Facts
8. All cells enter the first stage of the cell cycle after they are newly formed.
• This stage is called interphase.
• During interphase, cells grow and DNA duplicates and produces another
complete set of chromosomes.
• Then the cell begins the first of two stages of division.
9. Prophase I
• Genetic material untangles from a chromatin form into a form of condensed
chromosomes.
• Chromosomes become visible and ready to match up.
• They pair up with their homologue and form a tetrad.
• A tetrad is a four-stranded group of chromosomes joined at a point called
the centromere.
• Each chromosome has four chromatids.
• While the tetrad is being formed, centrioles move to opposite ends of the cell.
• The centrioles produce spindle fibers.
• The nuclear membrane starts to break apart.
10. Metaphase I
•
•
•
•
The tetrads migrate towards the center of the cell and line up.
They cross strands and exchange sections of DNA.
This is called crossing-over or gene swapping.
Crossing-over is important because it reorganizes the genetic information
on the sister chromosome.
• This ensures diversity in the germ cells.
11. Anaphase I
• The tetrads are pulled apart by the spindle fibers.
• Tetrads are pulled towards the poles at opposite ends of the cell.
• Each end now has two complete sets of chromosomes.
12. Telophase I
• The nuclear membrane reforms around the two separate groups
of chromosomes.
• Now the cytoplasm and organelles are divided up and the cell membrane
pinches the cell into two cells.
• This process is called cytokinesis.
• The result is two daughter cells each with the normal number of chromosomes.
• The chromosomes are now diverse because they have exchanged genetic
information.
8
Meiosis Video Quiz
Meiosis Fast Facts
Fast Facts
13. All cells now enter the second stage of the cell cycle.
14. Prophase II
• The chromatids are still in pairs attached at the centromere.
• The centrioles produce spindle fibers.
• The nuclear membrane starts to dissolve.
15. Metaphase II
• The chromatids move to the center of the cell to line up again.
• The spindle fibers attach to the centromere of each chromosome pair.
• The nuclear membrane dissolves completely.
16. Anaphase II
• The spindle fibers pull the chromosomes apart.
• The newly separated chromosomes travel to opposite ends of their cells.
• This separation guarantees diversity of the newly formed gametes.
17. Telophase II
• Nuclear membranes form around the two new sets of daughter
chromosomes.
• The cytoplasm and organelles divide.
• The cell membrane pinches the cells in half again.
• The result is four daughter cells and each contains half the chromosomes.
18. In meiosis, the cells are genetically different.
• During the first phase of meiosis, one cell divides into two cells.
• It is these two cells that then divide and become four new gametes.
• The cells are genetically different because of crossing-over and random
sorting of chromosomes.
• Each new cell that is created is a haploid cell.
9
Meiosis Video Quiz
Before Viewing
Activity 1
Name
Before Viewing Discussion
Teacher Note: Prior to viewing the program, ask the following questions to help students
focus on the topic. Space has been provided below for notes, additional questions, or their
reflections on this activity.
1. Why is meiosis important to all living things?
2. How are the two stages of meiosis similar/different from each other?
3. What are the steps of meiosis?
4. Why are there two distinct stages of cell division during meiosis?
5. How does meiosis guarantee similarities between generations of a species?
6. Why do offspring have characteristics from both parents?
7. How does meiosis guarantee diversity within a species?
NOTES:
10
Meiosis Video Quiz
Before Viewing
Activity 2
Name
Vocabulary
Teacher Note: Prior to watching the program, be sure to provide your students an
opportunity to become familiar with the following vocabulary words and their meanings.
1. reproduce
creation of an offspring from the cells
of two parents
2. gametes
sex cells; including sperm and eggs
3. germ cells
sperm and egg cells that allow
organisms to reproduce
4. zygote
a female germ cell that has been
fertilized by a male germ cell and
inherits one set of chromosomes from each parent
5. chromosomes
thread-like bodies in a cell’s nucleus that contain the genetic
information of that organism
6. meiosis
a process of cell division that allows organisms to reproduce
7. haploid cells
cells that contain only one set of chromosomes
8. diploid cells
cells than contain two sets of chromosomes, each set from each
parent
9. homologous chromosomes two chromosomes that are paired and have
information about the same trait
10. somatic cells
all cells besides egg or sperm cells
11. daughter cell
new cells with half the chromosome number of the parent cell;
human cells contain 23 chromosomes
12. tetrad
a four-strand group of chromosomes joined at a point
13. diversity
differences in species
14. parent cell
cell with a complete set of chromosomes before cell division;
human cells contain a complete set of 46 chromosomes
15. centromere
the region of the chromosome where two identical chromatids
are joined during meiosis
16. trait
a characteristic
17. crossing-over
an exchange of genetic material between two chromatids
18. cytokinesis
the separation of a cell into two new cells
19. chromatids
identical chromosomes that hold genetic material such as eye color
20. spindle fibers
aid in pulling the chromosomes apart towards opposite poles of
the cell
11
Meiosis Video Quiz
Before Viewing
Activity 3
Name
“I Want to Know” Questions
Teacher Note: Using the 5 W’s and HOW, allow students an opportunity to generate
questions they have about meiosis. Two examples have been provided. Periodically, revisit
and update the questions.
WHO
HOW
WHAT
What is meiosis?
MEIOSIS
WHY
WHEN
Why is meiosis
important to plants as
well as animals?
WHERE
12
Meiosis Video Quiz
During Viewing
Activity 1
Name
Sequencing Meiosis
Fill in the missing information to make the graphic organizer complete. A few examples
have been done for you.
Stage:
This is what happens:
Stage: Prophase I
Stage:
1
2
8
3
7
4
Stage:
Pairs of chromosomes
move to opposite
ends of the cell
towards poles
Stage:
Stage:
6
Stage: Metaphase II
5
Stage:
Nuclear membrane disintegrates;
chromosomes become attached to
spindle fibers at centromeres and
move toward center
13
Meiosis Video Quiz
During Viewing
Activity 2
Name
Meiosis Process
Graphic Organizer
Complete the graphic organizer.
There are two phases to the process of meiosis.
This process starts with ...
And the end result is ...
14
Meiosis Video Quiz
After Viewing
Activity 1
Name
Oh Golly, Miss Dolly Genes for Sale!
Dolly the sheep was the first successfully cloned
animal in 1997. Is genetic engineering a good
idea? Do we have the right to clone living things?
Are we morally obligated to develop genetically
engineered foods with the potential to feed everyone
on Earth? Or are we opening Pandora’s Box?
Research and prepare both sides of a controversial
issue that relates to genetics. Decide on two choices
that could possibly address the issue. List pros and cons for both sides. Decide which choice
would be the best one and write up a summary statement.
CHOICE #1:
Pro:
CHOICE #1:
Pro:
What’s
the Issue?
Con:
Con:
Summary statement:
15
Meiosis Video Quiz
After Viewing
Activity 2
Name
Dominant or Recessive?
Introduction – We all inherit genetic traits from our parents such as baldness, eye color,
color blindness, as well as blood type. This activity will help you investigate
which of the following traits are the result of dominant or recessive genes.
Directions – Look at each of the characteristics below. Decide which of the following traits
you inherited from your parents. Mark the trait that best describes you.
pigmented iris [Are your eyes dark or light?]
dark eyes (dominant)
light eyes (recessive)
hair type [Is your hair naturally curly or straight?]
mostly curly (dominant)
mostly straight (recessive)
little finger [Does your pinky finger bend inward toward your ring finger?]
bent (dominant)
straight (recessive)
tongue curling [Can you roll your tongue into a tube-like shape?]
can curl (dominant)
can’t curl (recessive)
ear lobes [Do your ear lobes hang free or are they attached?]
loose (dominant)
attached (recessive)
thumb crossing [When you clasp your hands together and interlock your
fingers, which thumb naturally is on top?]
left over right (dominant)
right over left (recessive)
hair on fingers [Do you have hair on one or more of the
middle segments of your fingers?]
hair on fingers (dominant)
no hair on fingers (recessive)
hitchhiker’s thumb [Do your thumbs bend backward to nearly a 90 ° angle?]
can’t bend (dominant)
can bend (recessive)
BONUS: After taking inventory of your genetic traits, tally up the results for your entire class.
Create various charts and graphs that share this information.
16
Meiosis Video Quiz
After Viewing
Activity 3
Name
Vocabulary Book
Use the following template to create a vocabulary book
for terms related to meiosis.
Vocabulary word
Illustration with labels
_________________________________
Pronunciation
_________________________________
Definition
_________________________________
_________________________________
_________________________________
_________________________________
_________________________________
Word used in a sentence
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
17
Meiosis Video Quiz
After Viewing
Quiz 1
Name
Meiosis Quiz
Circle the best answer for each question below.
1. The division of cells to create germ cells is called __________.
a. mitosis
b. cytokinesis
c. diploid split
d. meiosis
2. True or False: During meiosis, only one cell division takes place.
3. Homologous means _____________________________.
a. same trait with different information
b. same trait with the same information
c. different traits with the same information
d. different traits with different information
4. Chromosomes contain ____________________.
a. cells
b. diploid cells
c. genes, or genetic information
d. zygotes
5. True or False: When germ cells combine, they create life.
6. Meiosis divides one diploid cell into ____________________.
a. 4 diploid cells
b. 4 haploid cells
c. 2 haploid cells
d. 2 diploid cells
7. A gamete has ____________________.
a. 23 pairs of chromosomes
b. 46 chromosomes
c. 23 chromosomes
d. A and B
8. A zygote has ____________________.
a. 1 set of chromosomes
b. no chromosomes
c. 23 chromosomes
d. 2 sets of chromosomes
18
Meiosis Video Quiz
After Viewing
Quiz 1
Name
Meiosis Quiz (cont.)
9. Our traits are determined from ____________________.
a. our germ cells
b. our homologous cells
c. our chromosomes
d. None of the above
10. A germ cell is ____________________.
a. haploid
b. diploid
c. triploid
d. sometimes haploid, sometimes diploid, never triploid
11. Crossing over is when ____________________.
a. sister chromosomes entangle and exchange DNA strands
b. parent chromosomes entangle and exchange DNA strands
c. chromosomes split
d. daughter chromosomes split and form sister chromosomes
12. Meiosis II _________ the number of chromosomes of the parent cell.
a. maintains
b. doubles
c. reduces
d. triples
13. True or False: In meiosis, the resulting cells have 23 pairs of chromosomes while
in mitosis the resulting cells have 23 chromosomes.
14. When the cytoplasm and organelles divide at the end of meiosis I,
it is called __________________.
a. telophase I
b. cytokinesis
c. telekinesis
d. metaphase II
15. A tetrad is ____________________.
a. a chromosome with two chromatids
b. a chromosome with four chromatids
c. a chromosomes with no chromatids
19
Meiosis Video Quiz
After Viewing
Quiz 1
Name
Meiosis Quiz ( cont.)
16. Which is the very last phase of Meiosis?
a. metaphase II
b. anaphase I
c. telophase II
d. prophase II
17. Crossing over allows for ____________________.
a. more cells
b. less cells
c. each daughter cell to be identical
d. each daughter cell to be unique
18. In the second phase of Meiosis, or Meiosis II, the two daughter cells divide
into what?
a. 2 daughter cells with half the number of chromosomes
b. 4 daughter cells with half the number of chromosomes
c. 4 cousin cells with different chromosomes
19. True or False: The random sorting of chromosomes during anaphase II helps
create unique gametes.
20. Which of the following are differences between mitosis and meiosis?
a. Number of times the cells divide
b. Number of chromosomes in the parent cells
c. Exchange of genetic information
d. A and C
20
Meiosis Video Quiz
After Viewing
Quiz 2
Name
Vocabulary Quiz A
Choose the vocabulary word to make each statement correct.
A. REPRODUCE
creation of an offspring from
cells of two parents
B. GAMETES
C. GERM CELLS
sperm and egg cells that allow organisms to reproduce
D. ZYGOTE
a female germ cell that has been fertilized by a male
germ cell and inherits one set of chromosomes from
each parent
E. CHROMOSOMES
thread-like bodies in a cell’s nucleus that contain the
genetic information of that organism
F. MEIOSIS
a process of cell division that allows organisms to
reproduce
G. HAPLOID CELLS
H. DIPLOID CELLS
cells that contain two set of chromosomes, each set
from each parent
I. HOMOLOGOUS
CHROMOSOMES
J. SOMATIC CELLS
two chromosomes that are paired and have
1. The reproductive cells of the male (sperm) and female (eggs) are referred to as the
______________________.
2. All of an organism’s cells except the sperm or egg are ___________________.
3. Cells that contain only one set of chromosomes are ___________________.
4. A fertilized egg that has inherited a set of haploid cells from each parent is known
as a(n) ____________________.
5. ______________ is a cell dividing process that only occurs in an organism’s sex cells.
6. A set of __________________________________________ pair up with the same type
to determine such things as eye color or hair type in the offspring.
7. It’s the genetic information in your ________________________ that determines what
you look and sound like.
8. Two parents combine their sperm and egg cells in order to ___________________.
9. Cells that enable organisms to have offspring are called ___________________.
10. Cells that contain the full number of chromosomes are called ___________________.
21
Meiosis Video Quiz
After Viewing
Quiz 3
Name
Vocabulary Quiz B
A. TRAIT
a characteristic
B. DAUGHTER CELL
new cells with half the chromosome
number of parent cells; human cells
contain 23 chromosomes
C. TETRAD
D. DIVERSITY
E. PARENT CELL
cell with a complete set of chromosomes before cell
division; human cells contain a complete set of
46 chromosomes
F. CENTROMERE
the region of the chromosome where two identical
chromatids are joined during meiosis
G. CROSSING OVER
an example of genetic material between
two chromatids
H. CYTOKINESIS
I. CHROMATIDS
identical chromosomes that hold genetic material
such as eye color
J. SPINDLE FIBERS
aid in pulling the chromosomes apart towards
opposite poles of the cell
1. Eye color is a(n) _________________ that is passed on from parent to child.
2. The ____________________ will receive half of the chromosomes from the parent cell.
3. During the early stages of meiosis, each chromosome is made of two identical
________________ that share identical genetic material such as hair color and height.
4. The process of ________________________ ensures that the genetic material from two
parents will be exchanged, making the offspring similar yet unique.
5. Before cell division, each _____________________ has a complete set of chromosomes.
6. Species that display a lot of _____________________, or differences in characteristics,
are more likely to survive.
7. The separation of one cell into two new cells is known as _______________________.
8. _____________________ are chromosomes with four chromatids.
9. The region of the chromosome where two identical chromatids are joined during
meiosis is called the _______________________.
10. ________________________ help chromosomes migrate to opposite ends of the cell
22
during meiosis.
Meiosis Video Quiz
Suggested Reading List
Additional
Resources
Bodmer, Walter. The Book of Man: The Human Genome Project and the Quest to Discover
Our Genetic Heritage.
The author covers a lot of scientific ground in this book, from Gregor Mendel’s discovery
of the laws of inheritance to modern high-tech forensic science. Also explores the oftencontroversial topic of genetic engineering.
Dennis, Carina and Richard Gallagher. The Human Genome.
Mapping and sequencing of the human genome is considered by many to be
humankind’s most important scientific discovery. Beautiful illustrations embellish this
book as it takes the reader on a journey through everything from genetics and basic
biology to a number of key players plus the political/social/ scientific impact of this
incredible project.
Klotzko, Arlene Judith, editor. The Cloning Sourcebook.
This book is for the general reader as well as specialists in the field. Includes
contributions from scientists who are responsible for some of the groundbreaking
milestones in the development of cloning. Discusses cloning humans (for reproduction
and for therapies), pets, and other animals.
Scientific American. Understanding Cloning.
This book is one of four titles in the Pocket Science series from the editors of Scientific
American science magazine. This book is a collection of essays on various topics relating
to cloning. Asks thought provoking questions such as, “Should cloning be used to aid
endangered species?” and “Can cloning help us equip old brains with new bodies?”
Snustad, D. Peter and Michael J. Simmons. Principles of Genetics.
This text makes a great first course in the study of genetics. Superb photography allows
the reader to take hold of even the most complex of details. Discusses the Human
Genome Project, gene therapy, plus behavior genetics. Stresses key points, provides
various questions and answers, includes unique conversations with researchers.
Wilmut, Ian, Keith Campbell, and Colin Tudge. The Second Creation: Dolly and the Age of
Biological Control.
Human cloning is today’s hot topic. This book provides the reader an opportunity to
explore a scientific model for studying the interactions of genes and what surrounds
them.
23
Meiosis Video Quiz
Internet Sites
Additional
Resources
Below is a list of sites that you may use to find more information about meiosis. Due to
routine web maintenance, not all of the links will be accurate at the time
of access. If the link is not available, try to conduct a search on that topic from
the main site or from a search engine.
http://www.biology.arizona.edu/cell_bio/tutorials/meiosis/main.html
This site will help your students to better understand the sequence of events that take place
in the process of meiosis. Wonderful step-by-step tutorial.
http://www.accessexcellence.org/AB/GG/meiosis.html
Graphics are a strength at this site. Clear, outline format that explains the steps of meiosis.
http://www4.ncsu.edu/unity/users/b/bnchorle/www/
This is a great tutorial that simplifies the confusing but important steps of the process.
Attractive black background sets the stage for understanding clear graphics explaining the
details.
http://www.rothamsted.bbsrc.ac.uk/notebook/courses/guide/meiosis.htm
This site includes a wonderful animation that breaks the stages on meiosis into clear and
simple steps. Each frame has a short description of the action that is taking place.
http://www.johnkyrk.com/meiosis.html
Contains colorful animations with stages highlighted that gives a visual explanation of what
happens during the process of meiosis. One of the best sites out there in terms of animation
presentation.
http://tutor.lscf.ucsb.edu/mcdb/tutorial/meiosis/
A bit more advanced and goes into greater detail than some of the other sites.
http://www.pbs.org/wgbh/nova/baby/divide.html/
This site does a wonderful job of comparing two colorful action packed animations. It very
clearly shows the difference between the stages of meiosis and mitosis.
http://genetics-eductiona-partnership.mbt.Washington.edu/default.htm
Includes various education guides and instructional materials for classroom use. Also, PDF
files for download and suggested genetics web resources.
http://stats.bls.gov/k12/html/edu_over.htm
Links to various career sites covering science and genetics related careers. Includes teacher’s
guide, career information, and educational resources.
http://www.newscientist.com/hottopics/cloning/
Contains up to date articles that pertain to the latest advancements in science.
24
Meiosis Video Quiz
Answer Key - During Viewing Activity Sheet 1
Sequencing Meiosis
Fill in the missing information to make the graphic organizer complete. A few examples
have been done for you.
Stage: Metaphase I
Stage: Prophase I
Chromosomes condense;
nuclear membrane
disappears; crossover may occur
Stage: Telophase II
Nuclear membrane
forms around newly
divided chromosomes;
chromosomes begin
to fade; cytokinesis
occurs again
1
Chromosomes align in
the middle of the cell; two
chromosomes to each
spindle fiber
2
8
3
7
4
Stage: Anaphase I
Pairs of chromosomes
move to opposite
ends of the cell
towards poles
Stage: Telophase I
Stage: Anaphase II
Cytokinesis occurs
(cell pinches into two
new daughter cells)
Centromeres split
and chromatids
move to the poles
6
Stage: Metaphase II
Chromosomes line
up in middle of cell
5
Stage: Prophase II
Nuclear membrane disintegrates;
chromosomes become attached to
spindle fibers at centromeres and
move toward center
25
Meiosis Video Quiz
Answer Key - During Viewing Activity Sheet 2
Meiosis Process
Graphic Organizer
Complete the graphic organizer.
There are two phases to the process of meiosis.
This process starts with ...
Interphase
Prophase I
Metaphase I
Prophase II
Telophase I
Anaphase I
Metaphase II
Anaphase II
Telophase II
And the end result is ...
the production of eggs and sperm for sexual
reproduction.
26
Meiosis Video Quiz
Answer Key - After Viewing Quiz 1
Meiosis Quiz
1. The division of cells to create germ cells is called __________.
a. mitosis
b. cytokinesis
c. diploid split
d. meiosis
2. True or False: During meiosis, only one cell division takes place.
3. Homologous means _____________________________.
4. Chromosomes contain ____________________.
a. cells
b. diploid cells
d. zygotes
6. Meiosis divides one diploid cell into ____________________.
a. 4 diploid cells
b. 4 haploid cells
c. 2 haploid cells
d. 2 diploid cells
7. A gamete has ____________________.
b. 46 chromosomes
c. 23 chromosomes
d. A and B
8. A zygote has ____________________.
b. no chromosomes
c. 23 chromosomes
27
Meiosis Video Quiz
9. Our traits are determined from ____________________.
a. our germ cells
b. our homologous cells
c. our chromosomes
10. A germ cell is ____________________.
a. haploid
b. diploid
c. triploid
d. sometimes haploid, sometimes diploid, never triploid
11. Crossing over is when ____________________.
12. Meiosis II _________ the number of chromosomes of the parent cell.
a. maintains
b. doubles
c. reduces
d. triples
13. True or False: In meiosis, the resulting cells have 23 pairs of chromosomes while
in mitosis the resulting cells have 23 chromosomes.
it is called __________________.
a. telophase I
b. cytokinesis
c. telekinesis
d. metaphase II
15. A tetrad is ____________________.
a. a chromosome with two chromatids
b. a chromosome with four chromatids
c. a chromosomes with no chromatids
28
Meiosis Video Quiz
a. metaphase II
b. anaphase I
c. telophase II
d. prophase II
17. Crossing over allows for ____________________.
a. more cells
b. less cells
c. each daughter cell to be identical
d. each daughter cell to be unique
18. In the second phase of Meiosis, or Meiosis II, the two daughter cells divide
into what?
19. True or False: The random sorting of chromosomes during anaphase II helps
create unique gametes.
20. Which of the following are differences between mitosis and meiosis?
d. A and C
29
Meiosis Video Quiz
Vocabulary Quiz A
Choose the vocabulary word to make each statement
correct.
A. REPRODUCE
creation of an offspring from
cells of two parents
B. GAMETES
C. GERM CELLS
sperm and egg cells that allow organisms to reproduce
D. ZYGOTE
a female germ cell that has been fertilized by a male
germ cell and inherits one set of chromosomes from
each parent
E. CHROMOSOMES
thread-like bodies in a cell’s nucleus that contain the
genetic information of that organism
F. MEIOSIS
a process of cell division that allows organisms to
reproduce
G. HAPLOID CELLS
H. DIPLOID CELLS
cells that contain two set of chromosomes, each set
from each parent
I. HOMOLOGOUS
CHROMOSOMES
J. SOMATIC CELLS
two chromosomes that are paired and have
1. The reproductive cells of the male (sperm) and female (eggs) are referred to as the
gametes
______________________.
somatic cells
2. All of an organism’s cells except the sperm or egg are ___________________.
haploid cells
3. Cells that contain only one set of chromosomes are ___________________.
4. A fertilized egg that has inherited a set of haploid cells from each parent is known
zygote
as a(n) ____________________.
meiosis is a cell dividing process that only occurs in an organism’s sex cells.
5. ______________
homologous chromosomes
6. A set of __________________________________________
pair up with the same type
to determine such things as eye color or hair type in the offspring.
chromosomes
7. It’s the genetic information in your ________________________
that determines what
you look and sound like.
reproduce
8. Two parents combine their sperm and egg cells in order to ___________________.
germ cells
9. Cells that enable organisms to have offspring are called ___________________.
30
diploid cells
10. Cells that contain the full number of chromosomes are called ___________________.
Meiosis Video Quiz
Vocabulary Quiz B
A. TRAIT
a characteristic
B. DAUGHTER CELL
new cells with half the chromosome
number of parent cells; human cells
contain 23 chromosomes
C. TETRAD
D. DIVERSITY
E. PARENT CELL
cell with a complete set of chromosomes before cell
division; human cells contain a complete set of
46 chromosomes
F. CENTROMERE
the region of the chromosome where two identical
chromatids are joined during meiosis
G. CROSSING OVER
an example of genetic material between
two chromatids
H. CYTOKINESIS
I. CHROMATIDS
identical chromosomes that hold genetic material
such as eye color
J. SPINDLE FIBERS
aid in pulling the chromosomes apart towards
opposite poles of the cell
trait
1. Eye color is a(n) _________________
that is passed on from parent to child.
daughter cell will receive half of the chromosomes from the parent cell.
2. The ____________________
3. During the early stages of meiosis, each chromosome is made of two identical
chromatids that share identical genetic material such as hair color and height.
________________
crossing over ensures that the genetic material from two
4. The process of ________________________
parents will be exchanged, making the offspring similar yet unique.
parent cell has a complete set of chromosomes.
5. Before cell division, each _____________________
diversity
6. Species that display a lot of _____________________,
or differences in characteristics,
are more likely to survive.
cytokinesis
7. The separation of one cell into two new cells is known as _______________________.
tetrad
8. _____________________
are chromosomes with four chromatids.
9. The region of the chromosome where two identical chromatids are joined during
centromere
meiosis is called the _______________________.
Spindle fibers help chromosomes migrate to opposite ends of the cell
10. ________________________
during meiosis.
31
Meiosis Video Quiz
Script
CAST
Professor Science ....................................................host
Victor Velocity............................................racecar driver
Quiz Clown ............................................................clown
Ricky Wave ................................................................DJ
Star Struck ..........................................................reporter
Fizzle ........................................................................genie
Wendy River ........................................................cowgirl
Nuke Rockney ......................................................coach
Sandy Space ....................................................astronaut
Salty Gales ............................................................pirate
Quizitor ....................................................................robot
SCENE 1
PROFESSOR SCIENCE
Hello there! Welcome to another wacky episode of the Wonderful World of
Science, starring…. Me, PROFESSOR SCIENCE!! Today’s topic is about
division! No, not the mathematical kind of division, we are talking a type of
cell division – Meiosis!! Yeah, yippee!! Don’t worry; by the end of this show
you’ll be as crazy about Meiosis as I am!! With the help of a few friends who
will quiz you on the main topics, this whole Meiosis thing will be a breeze!!
Meiosis is a process of cell division, but not just any cell division. You may
have heard of mitosis, the division of regular somatic cells. Meiosis produces
different cells, the cells that allow organisms to reproduce. These cells are
called germ cells.
Before we can get into Meiosis, let me give you a little background on
chromosomes. Every living thing is made of cells. Inside these cells are
chromosomes. Chromosomes contain genetic information, or genes, that
determine who you are and what you look like; they even determine if you
are a boy or a girl!
32
Meiosis Video Quiz
Script
Every organism has a certain number of chromosome pairs in their cells. For
example, onion plants have 8 pairs of chromosomes. Tomato plants have 12
pairs. Goldfish have 47 pairs, and humans have 23 pairs of chromosomes.
The chromosome number of an organism isn’t related to its size or
composition. Let’s take a look! A giant sequoia tree can grow to a height of
about 250 feet, and it has 22 chromosomes. Grasshoppers are about two
inches long, and have 24 chromosomes.
Chromosomes come in pairs; one chromosome comes from your mother and
the other from your father. Your paired chromosomes are called homologous
because both chromosomes have information about the same trait or
characteristic, like eye color. But, the information is different for each
characteristic because it is coming from two different people!
Since the chromosomes in the pair come from different people, this is how our
traits are determined. This is also what makes us individuals. It’s kind of like
having two sets of instructions to put a bike together, one from the bike
manufacturer and one from the manufacturer of another type of bike. Both
instructions tell you how to assemble the bike. One instruction sheet might
suggest larger tires and the other might say to add fenders. So the bike turns
out differently than each sheet said because you took information from two
different sheets and combined them.
Now, these chromosome pairs are very important. In order for a cell to
function properly, it must have one pair of each type of chromosome. This
means, for a human cell to work, it must have 23 pairs of chromosomes. A
cell that has the full number of chromosomes is called a diploid cell. Almost
all of the cells in the human body are diploid. Your heart, bone and skin cells
are all diploid, having 46 chromosomes total. Scientists refer to the diploid
chromosome number as “2N.” This represents the total number of
chromosomes in the cell, which is the number of chromosome pairs, multiplied
by 2!
For example, a fruit fly has 4 pairs of chromosomes. What is its diploid
chromosome number? Think! That’s right! A fruit fly has a diploid number of
8 because it has four pairs, multiplied by two, equaling eight! Great job! Let’s
move on, geniuses!
33
Meiosis Video Quiz
Script
Now, if a cell had only one of each type of chromosome in it, it would be
called a haploid cell. Your haploid cells only have 23 chromosomes total. This
is where meiosis comes in!
SCENE 2
PROFESSOR SCIENCE
Meiosis is extremely important! Why, without it, none of us would exist!!
Most organisms need meiosis to reproduce! Meiosis only takes place in the
reproductive organs. The cells that Meiosis creates are essential for the
reproduction process. You see, meiosis is the division of cells to create a
special kind of cell, a germ cell.
Meiosis divides a diploid cell into four haploid cells by going through two
divisions. So from one somatic cell, the division produces four germ cells that
can be used in reproduction.
A haploid cell has half of the chromosomes as a diploid cell. These special
germ cells are called gametes. So, at the end of meiosis, each human gamete
has a total of 23 chromosomes. Scientists symbolize the haploid chromosome
number by using an “N.” Just like the diploid symbol, N represents the
number of chromosomes.
If a guinea pig has 64 chromosomes in each of its diploid cells, what would
be its haploid cell number or “N”? I’ll give you a few seconds, good luck!
(pause for a few seconds) Got it? The answer is 32! Because there are 64
total, you have to cut that number in half!
It is important for the gamete to have only half of the proper number of
chromosomes because when two gametes fuse during fertilization, their
chromosomes pair up and total 46, or 23 pairs. Two fused germ cells create
a zygote with two sets of chromosomes. A zygote is a female germ cell that
has been fertilized by a male germ cell. From that zygote, an offspring
develops.
All right! Let’s take a break and answer some questions. When we come
back, we will learn the stages of meiosis. Are you ready for the first round
of questions?! Good Luck!!
34
Meiosis Video Quiz
Script
SCENE 3
VICTOR VELOCITY
Vroom, Vroom, Vroom, Screeeech!!!!!!!!!!! Whew! Looks like I stopped by
just in the nick of time! I’ve got a quick question for you and then it’s back
to the race!!
1. The division of cells to create germ cells is called__________.
a. Mitosis
b. Cytokinesis
c. Diploid split
d. Meiosis
What a way to start off the quiz! I hope you wrote down an answer. Now
get in gear and move to the next question.
QUIZ CLOWN
Boy! Balancing on a high wire with these big shoes on sure is hard work!
While I take a balance break, see if you can answer this!
2. True or False: During Meiosis, only one cell division takes place.
Hmmm. Write down your answer and let’s move on to the next question.
My feet are cramping up in these shoes!
RICKY WAVE
Hello faithful listeners of SQRD- science quiz radio. Ricky Wave here to
bring you the latest sounds from the underground. So tune in to…
3. Homologous means ________________________________.
Lots of words, but it had a great beat. Write down your answer and let’s
tune into the next question!
35
Meiosis Video Quiz
Script
STAR STRUCK
Hi everyone, Star Struck at the latest movie premiere- “Meiosis and
Me.” I’m here to present… the next question!
4. Chromosomes contain __________________.
a. cells
b. diploid cells
d. zygotes
How did you do? Pick an answer and write it down. I’m off to do my
close-up now! How does my hair look?
FIZZLE
If you get my question right, I just may grant you three wishes!!
Hmmm. That’s very interesting. What do you think? Pick true or false
and get it on paper. Oh, I’ve gotta go! Someone is just taking a test
and is wishing for a good grade!
WENDY RIVER
Well, howdy! Before the roundup here, let’s lasso up a question for
y’all.
6. Meiosis divides one diploid cell into __________________.
a. 4 diploid cells
b. 4 haploid cells
c. 2 haploid cells
d. 2 diploid cells
Well, what do you think, pardner? Choose your answer wisely and
write it down. I’m off to lasso class, but I’ll see y’all a little later!
36
Meiosis Video Quiz
Script
NUKE ROCKNEY
(Blows whistle) Ok team, you are doing a great job! Keep up the good
work! Remember to use those brains! You know the answer to this!
7. A gamete has __________________.
b. 46 chromosomes
c. 23 chromosomes
d. A and B
Well, how did you do? Pick an answer and write it down. You can do it!
Go team go!
SANDY SPACE
Hi everyone, Sandy Space broadcasting live from the Space Station. Turn
on all your rocket boosters to answer this!
8. A zygote has __________________.
b. No chromosomes
c. 23 chromosomes
What do you think? Write your answer down while I call ground control.
SALTY GALES
Well, shiver-me-timbers, maties! Get this right and the treasure map of
knowledge is yours!
9. Our traits are determined from __________________.
a. Our germ cells
b. Our homologous cells
c. Our chromosomes
Aye, how did you do? Write yer answer down matey while I set sail with
me crew!
37
Meiosis Video Quiz
Script
QUIZITOR
Hello. I am Quizitor. Show me that you are a great scientist by answering this
question correctly! Good luck!
10. A germ cell is __________________.
a. Haploid
b. Diploid
c. Triploid
d. Sometimes haploid, sometimes diploid, never triploid
What do you think? Pick an answer and write it down. It’s time for me to log
off, but here’s Professor Science with more information. That is all.
SCENE 4
PROFESSOR SCIENCE
I’m back!! How were the questions? Not too bad, I imagine! Now, as you
probably remember from mitosis, scientists refer to the original cell as the
parent cell, the original pairs of chromosomes as sister chromosomes, the
new chromosomes as daughter chromosomes, and the new cells as daughter
cells.
Before we get to the specifics of meiosis, let’s review the stages of mitosis, or
regular cell division. Do you remember the four stages?! Think real hard!
(short pause) You got it! They are Prophase, Metaphase, Anaphase, and
Telophase.
Well, the cell cycle and the phases of mitosis are similar to meiosis! But there
are some important differences. As I just said, in mitosis, one cell divides into
two daughter cells, and in meiosis, one cell divides twice into four daughter
cells. In meiosis, the chromosomes can exchange parts. They don’t do that in
mitosis. The daughter cells in meiosis differ from each other, while the
daughter cells in mitosis are identical to their parent cell. And the most
important difference between the two is that in meiosis, the four daughter
cells have only 23 chromosomes in them, while in mitosis, each cell has 23
pairs.
38
Meiosis Video Quiz
Script
All cells enter the first stage of the cell cycle after they are newly formed. That
stage is called interphase. During interphase, cells grow, and DNA duplicates
to produce another complete set of chromosomes. When the cell is ready,
Meiosis begins the first division.
We number each phase, since the cells undergo two different divisions. In
prophase I, the genetic material untangles from chromatin form into
condensed chromosomes. The chromosomes become visible and ready to
match up. They then pair up with their homologue to form a tetrad. A tetrad
is a four-stranded group of chromosomes joined at a point called the
centromere. Basically, each chromosome has four chromatids. While the
tetrad is being formed, centrioles move to opposite ends of the cell to form
poles. The centrioles produce spindle fibers. Also in this early stage, the
nuclear membrane starts to break apart.
Metaphase I is next! The tetrads migrate towards the center of the cell, and
line up. While the tetrads are pairing off and lining up, they cross strands
and exchange sections of DNA. This is called crossing over. Crossing over, or
gene swapping as it is sometimes called, reorganizes the genetic information
on the sister chromosomes. This provides diversity in the germ cells. That’s
why you look similar to your siblings, but not identical!
In anaphase I, the tetrads are pulled apart by the spindle fibers. Now they
are pulled towards the poles at opposite ends of the cell, each end having
two complete sets, or 23 pairs of chromosomes.
Lastly, the cell moves into telophase I, where the nuclear membrane is
reformed around the two separate groups of chromosomes. At this point, the
cytoplasm and organelles are divided up, and the cell membrane pinches the
cell into two cells. This process is called cytokinesis. The result is two daughter
cells, each with the normal number of chromosomes. And remember, none of
these cells are identical to each other because the chromosomes have
exchanged genetic information.
39
Meiosis Video Quiz
Script
SCENE 5
PROFESSOR SCIENCE
Now the second phase of meiosis, or meiosis II begins. In prophase II, the
chromatids are still in pairs attached at the centromere. Once again, the
centrioles produce spindle fibers, and the nuclear membrane starts to dissolve.
Next, the chromatids move to the center of the cell to line up once more in
metaphase II. The spindle fibers attach to the centromere of each chromosome
pair. The nuclear membrane completely dissolves.
In anaphase II, the spindle fibers pull the chromosomes apart, and the newly
separated chromosomes travel to opposite ends of their cells. The key
difference from mitosis happens in this stage.
Remember how one chromosome from each pair is from the mother and one
from the father? Well, now the paired chromosomes are split up and sorted
randomly to opposite poles. Since only one chromosome of each pair ends up
at each pole, the diversity becomes much greater between the newly formed
gametes.
In the last stage, Telophase II, nuclear membranes form around the two new
sets of daughter chromosomes. The cytoplasm and organelles divide, and the
cell membrane pinches the cell in half once again. And there you have it – four
daughter cells, each with half the chromosome number!
Remember, during the first phase of meiosis, one cell became two cells. Both
of those cells went through the second phase to create a total of four new
gametes.
As I mentioned before, the neat thing about meiosis is that the cells are
genetically different. The crossing over of genetic information and the random
sorting of chromosomes ensure that each daughter cell is unique. Since each
new cell that is created is a haploid cell, the chromosome number is restored
during fertilization, and there will be even more genetic mixing!
And there you have meiosis! Pretty cool stuff, isn’t it? I know you have this
down pat and to prove it; here comes my friends to see how smart you are!
40
Meiosis Video Quiz
Script
SCENE 6
VICTOR VELOCITY
Vroom, Vroom, Vroom!!!!!!!!!! Time for a quick pit stop and another
question for you!
11. Crossing over is when __________________.
What do you think? Write down your answer and get back in the race!
QUIZ CLOWN
Hi again! You are just in the nick of time! I was about to have a pie thrown
in my face! Now that you’re here, it won’t happen! (whipped cream pie is
thrown at her). Or…I could be mistaken. Here’s a not so messy question for
you.
12. Meiosis II ________ the number of chromosomes of the parent cell.
a. maintains
b. doubles
c. reduces
d. triples
So, what do you know? Can you figure it out? Put your answer down and
wait right here for further instructions…(turns around, grabs pie and
pretends to throw pie at camera)
RICKY WAVE
Hello all you out there in radio land. Ricky Wave here bringing you the
latest tunes from the new band- MEIOSIS. Let’s listen…
13. True or False: In meiosis, the resulting cells have 23 pairs
of chromosomes while in mitosis the resulting cells have
23 chromosomes.
41
Meiosis Video Quiz
Script
That was fab-u-lous! I’m sure you’ve got an answer written down. Don’t
change that dial; we’ve got more great tunes ahead!
STAR STRUCK
Hello to all my fans out there! This is Star Struck bringing you the latest dish
from science quiz. I heard the following from a reliable source…
it is called __________.
a. Telophase I
b. Cytokinesis
c. Telekinesis
d. Metaphase II
Wow! That was some news! I hope you figured it out and wrote down an
answer. I’d love to hear it, but I just saw my favorite movie star in the world
and I have to get an autograph!
FIZZLE
I’m back! I just had to come out of my bottle for this next question!
15. A tetrad is __________________.
a. A chromosome with two chromatids
b. A chromosome with four chromatids
c. A chromosomes with no chromatids
Very interesting. What do you think? Write your answer down and I may
stay out of my bottle a little longer.
WENDY RIVER
Whew! That bronco was a tough one! While I try to catch my breath, let’s
see if you can rope this next problem!
42
Meiosis Video Quiz
Script
a. Metaphase II
b. Anaphase I
c. Telophase II
d. Prophase II
Hmm. How did you do? Put yer answer down and let’s saddle up for the
next rip-roaring question!
NUKE ROCKNEY
(Blows whistle) Ok team, this is kind of a tough play I’m about to show
you. But with some concentration, I’m sure you will all get it!
17. Crossing over allows for __________________.
a. More cells
b. Less cells
c. Each daughter cell to be identical
d. Each daughter cell to be unique
Go team go! You pick an answer and let’s get back in formation! Let’s
move it out!
SANDY SPACE
Sandy Space zooming in from outer space to give the next question.
Listen up!
18. In the second phase of Meiosis, or Meiosis II, the two daughter
cells divide into what?
d. none of the above
So what do you think? Write down an answer and I’ll boost you
on to the next question.
43
Meiosis Video Quiz
Script
SALTY GALES
Ahoy maties!! Another correct answer and you can be my first mate!
19. True or False: The random sorting of chromosomes during
anaphase II helps create unique gametes.
What’s yer answer? Write it down quick before me and my crew come
sailing after you!
QUIZITOR
Hello. I am Quizitor. I’ll take break from my latest experiment to quiz you!
Hope you all get this one right!
20. Which of the following are differences between mitosis
and meiosis?
d. A and C
Get your final answer down. It’s time again to see Professor Science.
Thank you. This is Quizitor— logging off.
44
Meiosis Video Quiz
Script
SCENE 7
PROFESSOR SCIENCE
Hey, you did it! You are so smart! Well, that is all I have for you today on the
Wonderful World of Science! Stay tuned for a complete list of answers. See you
next time!!
ANSWERS
1.
d.
2. False.
The division of cells to create germ cells is called meiosis.
A gamete is the result of a germ cell dividing twice.
3.
a.
Homologous means same trait with different information.
4.
c.
Chromosomes contain genes, or genetic information.
5.
True.
6.
B.
Meiosis divides one diploid cell into 4 haploid cells.
7.
c.
A gamete has 23 chromosomes.
8.
d.
A zygote has 2 sets of chromosomes.
9.
c.
Our traits are determined from our chromosomes.
10.
a.
A germ cell is haploid.
11.
a.
Crossing over is when sister chromosomes entangle
and exchange DNA strands.
12.
c.
Meiosis II reduces the number of chromosomes of the
parent cell.
13. False.
When germ cells combine, they create life.
In meiosis, the resulting cells have 23 chromosomes while
in mitosis, the resulting cells have 23 pairs of chromosomes.
14.
b.
When the cytoplasm and organelles divide at the end
of meiosis I, it is called cytokinesis.
15.
b.
A tetrad is a chromosome with four chromatids.
16.
c.
Telophase II is the very last phase of Meiosis.
17.
d.
Crossing over allows for each daughter cell to be unique.
18.
b.
In the second phase of Meiosis, or Meiosis II, the two
daughter cells divide into 4 daughter cells with half the
number of chromosomes.
19.
True.
Random sorting of chromosomes increases gamete diversity.
20.
d.
Mitosis and meiosis differ in the number of cell divisions and
in the exchange of genetic information.
45
Meiosis Video Quiz

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