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TEKS 6 E
Meiosis and Mitosis
TAKS Objective 2 – The student will demonstrate an understanding of
living systems and the environment.
TEKS Science Concepts 6 E
The student knows the structures and functions of nucleic acids in the
mechanisms of genetics. The student is expected to
(A) compare the processes of mitosis and meiosis and their
significance to sexual and asexual reproduction
TAKS Objective 2
page 1
TEKS 7.9 A
For Teacher’s Eyes Only
Mitosis and Meiosis
Student Prior Knowledge
Students should be familiar with the components associated with body systems
TEKS 6.10 (C) identify how structure complements function at different levels of
organization including organs, organ systems, organisms, and populations and the
functions of these systems.
TAKS Objective 2
page 2
TEKS 7.9 A
Meiosis
5 E’s
ENGAGE
Mitosis/Meiosis Dance
GET THIS FROM PAM
EXPLORE
Explore 1
Mitosis, Meiosis and Fertilization Teacher Prep Notes
By Dr. Scott Poethig, Ingrid Waldron and Jennifer Doherty, Department of Biology, University of Pennsylvania, 2007 1
Equipment and Supplies:
Sockosomes (1 per student or 4 per group -- see chart on page 2)
Optional: string to represent spindle fibers
Sockosome supplies:
Small or medium children’s socks (no more than half of any one color; even
number of pairs of each color sock; preferably half small and half medium or
otherwise all of one size)
Fiber fill
Small squares or circles of Velcro
1
These teacher preparation notes and the related student handout are available at
http://serendip.brynmawr.edu/sci_edu/waldron.
TAKS Objective 2
page 3
TEKS 7.9 A
Needle and thread or fabric glue
Masking tape and Sharpies
Teacher Preparations:
To produce sockosomes
1. Sew (or glue) one-half of a piece of Velcro (the fuzzy half) to the heel
of one sock, and sew the other half (the part with hooks) to the heel of
the other sock.
2. Fill each sock with fiber fill, and sew the end of each sock closed
(sewing works much better than gluing for this step).
3. Stick the socks together at the heels. You now have a chromosome
with two chromatids, where each sock represents a chromatid.
4. Pairs of homologous chromosomes will be represented by two
sockosomes of the same color, one with a stripe marked along the
length of each sock with a permanent marker (representing the
different alleles on the two homologous chromosomes). Add a ring of
tape around each sock in each sockosome to represent a gene that is
inherited by simple Mendelian transmission. For each pair of
homologous sockosomes, label the tape on each sockosome with a
different allele of the same gene. For example:
Albinism (a)
(Albino)
Albinism (A)
(Pigmented skin)
Obviously the allele labeled on both socks in a single sockosome
should be the same.
Use the chart on the next page to guide you, as you label half the pairs
of homologous sockosomes of each color with the alleles for skin
pigmentation (A for pigmented skin and a, the albino allele) and label
the other half of the pairs of homologous sockosomes of each color
with the alleles for thumb bending (H and h). If half of your socks are
small and half medium, then all of the small socks should be labeled
with an A or a, and all of the medium socks should be labeled with an
H or h.
TAKS Objective 2
page 4
TEKS 7.9 A
Sockosomes Needed for Two Groups of Four Students Each
Mitosis &
Meoisis
Activities -Group 1
a sockosome in
solid color 1
A sockosome in
the solid color 1
but with a stripe
h sockosome in
solid color 2
H sockosome in
solid color 2 but
with a stripe
Mitosis &
Meoisis
Activities -Group 2
h sockosome in
solid color 1
H sockosome in
the solid color 1
but with a stripe
a sockosome in
solid color 2
A sockosome in
solid color 2 but
with a stripe
The same sockosomes can be used for these two groups of students for the final
activity which models meiosis followed by fertilization, but for this activity one
group should have all the a and A sockosomes, and the other group should have
all the h and H sockosomes. The pair of sockosomes in one color will represent
the mother's chromosomes, and the pair of sockosomes in the other color will
represent the father's chromosomes. The different colors for the mother’s and
father's sockosomes represent the fact that, although the labeled alleles are the
same for the mother’s and father’s chromosomes, there are many genes on each
chromosome and the mother’s and father’s chromosomes will have different
alleles for many of these genes.
Additional Possible Activities
Sockosomes made with larger socks can be modified so they can be used to model
crossing over and recombination. Using a larger pair of socks, cut off a portion of
the top of the sock to be stuffed and sewed close separately. The top portion can
then be reattached with Velcro, allowing it to be removed and swapped with the
top portion of another sock. This can be particularly useful for lecture
demonstrations.
We have found the video "Cell Division: Mitosis and Cytokinesis" to be an
excellent overview of the subject. It is available for purchase from
http://www.cytographics.com/ for AUD$89. We recommend showing it after the
mitosis portion of the Mitosis, Meiosis and Fertilization activity as a review of the
subject.
TAKS Objective 2
page 5
TEKS 7.9 A
Explore 2
Mitosis/Meiosis Manipulative
GET THIS FROM PAM
Students will use a hand-on manipulative to take a cell from the beginning of
meiosis to the end of meiosis. They will also do the same for mitosis and
compare the two events.
EXPLAIN REWRITE
Complete the Meiosis PowerPoint presentation with your student with
discussion and the completion of the following questions.
ELABORATE
Elaboration 1
Student will complete a Flow Chart comparing Mitosis and Meiosis.
Elaboration 2
Students will complete a chromosome number worksheet to compare mitosis
and meiosis, as well as, solidify the haploid/diploid concepts of the two types of
nuclear division.
EVALUATE
TAKS Objective 2
page 6
TEKS 7.9 A
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Mitosis, Meiosis, and Fertilization
by Dr. R. Scott Poethig, Dr. Ingrid Waldron, and Jennifer Doherty
Department of Biology, University of Pennsylvania, © 20072
Mitosis -- How Your Body Makes New Cells
How many cells do you think your body has?
Why does your body need to have lots of cells?
Each of us began as a single cell, so one important question is:
How did that single cell develop into a body with more than a trillion cells?
The production of such a large number of body cells is accomplished by many, many repeats
of a cycle of cell division in which one cell gives rise to two cells, each of which in turn gives
rise to two cells, etc. Thus, cell division is needed for growth.
Even in a fully grown adult, cells still undergo cell division. Why is this useful? Think about
your skin, for example.
The two cells that come from the division of one cell are called daughter cells. (It may seem
odd, but the cells produced by cell division are called daughter cells, even in boys and men.)
Each of the daughter cells needs to have a complete set of chromosomes. What are
chromosomes? Why does each cell need a complete set of chromosomes?
How do you think each daughter cell gets a complete set of chromosomes?
2
Teachers are encouraged to copy this student handout for classroom use. A Word file, which can be used to prepare a modified version if
desired, and Teacher Preparation Notes are available at http://serendip.brynmawr.edu/sci_edu/waldron/.
8
In each cycle of cell division, the cell first makes a copy of all of the DNA in each of the
chromosomes, as shown in the figure below.
(Adapted from Figure 9.9 in Biology by Johnson and Raven)
After the DNA in each chromosome has been copied, the cell undergoes a type of cell division
called mitosis, which carefully separates the two copies of each chromosome to opposite
ends of the dividing cell, so each daughter cell ends up with a complete set of chromosomes.
Mitosis -- The Basics
Once the DNA of a chromosome has been copied, the two copies of the DNA form two chromatids
which are attached to each other at the centromere. These chromatids are often called sister
chromatids because they are identical. (The two attached chromatids are called sister chromatids,
even in the cells of boys and men.) During mitosis the two chromatids of a chromosome separate and
become independent chromosomes; one of these chromosomes goes to each daughter cell.
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Chromatids
Cell
Chromosome
Chromosomes
Cell
Cell 1
Cell 2
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To keep things simple, we will begin by discussing mitosis in a cell which has only two
chromosomes. These two chromosomes are a pair of homologous chromosomes. Both
homologous chromosomes contain genes which control the same traits (e.g. eye color and
skin color). For each gene on a pair of homologous chromosomes, there may be two different
versions or alleles of the gene on the two different homologous chromosomes (e.g. an allele
for brown eyes on one chromosome and an allele for blue eyes on the other chromosome). In
contrast, the two sister chromatids of a chromosome have identical alleles of each gene,
because the process of copying DNA results in exact copies of the original alleles.
You will model mitosis using a pair of sockosomes to represent the pair of homologous
chromosomes. Each sockosome will have two socks joined at the heel to represent the sister
chromatids in a chromosome after the DNA has been replicated. The pair of sockosomes will
look like the chromosomes in the diagram on page 2.
1. Inside a cell, each chromatid consists of a single long molecule of _____________.
Are the alleles in the sister chromatids in a chromosome identical or different?
Are the alleles in the two homologous chromosomes identical or different?
2. Both sockosomes are the same color, to indicate that you have a pair of homologous
chromosomes which both have the same genes. As shown in the figure on page 2, one of
your sockosomes has a stripe on both socks and the other sockosome has no stripes; this
indicates that the two homologous chromosomes have different alleles, even though they have
the same genes.
What is wrong with the diagram shown below? Explain why sister chromatids could not
have different alleles.
Chromatids
Cell
Chromosome
11
3. Together with your partner, use your sockosomes to demonstrate how the two
chromosomes line up at the beginning of mitosis. Then demonstrate how the sister chromatids
of each chromosome separate during mitosis and become separate chromosomes, one of
which goes to each daughter cell.
4. Before the cells produced by mitosis can divide again, what has to happen to the
chromosomes in each cell?
Draw what the chromosomes in each cell
will look like when the cell is ready to
undergo the next round of mitosis. Label
the chromosomes and chromatids.
Cell
12
The next section describes how mitosis is accomplished in a real live
human cell and how this process ensures that each daughter cell receives
a normal, complete set of chromosomes.
Mechanics of mitosis
In a living cell, when the cell is carrying out its normal activities, the DNA
molecule of each chromosome is a long tangled thread. Each human cell
has 46 chromosomes (23 pairs of homologous chromosomes). Obviously,
it would be difficult to reliably separate the two copies of each of 46 long
tangled DNA molecules. Therefore, in preparation for mitosis, the DNA is
condensed into compact chromosomes, like those shown in the diagram
on page 2.
The basic steps of mitosis, which ensure that each daughter cell receives
a complete set of chromosomes, are as follows.
1. DNA is copied (called replication).
2. DNA is condensed into compact chromosomes (each with two sister
chromatids); these are easier to move than the long tangled DNA. Spindle
fibers which will move the chromosomes begin to form.
3. Spindle fibers line the chromosomes up in the middle of the cell.
4. Spindle fibers shorten to pull the sister chromatids apart toward
opposite ends of the cell.
5. The cell begins to pinch in half, with one set of chromosomes in each
half.
6. Two daughter cells are formed.
For each of the figures below, give the number of the corresponding stage
described above. Draw arrows to indicate the sequence of events during
mitosis. (For simplicity, the figures show cells that have only 4
chromosomes (2 pairs of homologous chromosomes), but the basic
process is the same as in human cells which have 46 chromosomes.)
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separating
chromosomes
Sister chromatids are shown in two of these drawings; label each pair of
sister chromatids (SC).
Pairs of homologous chromosomes are shown in four of these drawings;
circle and label each pair of homologous chromosomes (HC).
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Chromosomes and Genes in Human Cells
The figure on the left shows a karyotype, which is a photograph of a
magnified view of the chromosomes from a human cell that was ready to
begin mitosis. Each chromosome has condensed double copies of its
DNA, contained in a pair of sister chromatids linked by a centromere.
Adapted from Concepts of Genetics 8e
by Klug, Cummings, and Spencer
In a karyotype, the complete set of chromosomes is organized in
homologous pairs and numbered. Each numbered pair of homologous
chromosomes carries a specific set of genes. For example, both copies of
human chromosome 11 have a gene for the production of the pigment
melanin (a molecule that contributes to our skin and hair color), but one
may have the A allele for normal melanin production and skin color, while
the other may have the little a allele. If both chromosomes have the little a
allele, the body's cells do not produce melanin, which results in albinism
(the white skin and hair color shown in the figure above).
Use your sockosomes to model mitosis in a cell which has two pairs of
homologous chromosomes. All of your sockosomes have labeled
masking tape genes. Find two sockosomes in your group that have the
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two different alleles for the gene for albinism (A for normal melanin
production and skin color and a for albinism). Next, find two sockosomes
in your group that have the two different alleles for the gene for thumb
bending (H for straight thumb and h for the hitchhiker’s thumb; you have a
hitchhiker’s thumb if you can bend the top part of your thumb backwards
more than 45º). Put these four sockosomes in a pile which will represent
the two pairs of homologous chromosomes, each with the DNA copied, so
the cell is ready to undergo mitosis. Model the steps in mitosis. Begin by
arranging the sockosomes in the pattern observed for chromosomes in a
real cell at the beginning of mitosis (see diagram on previous page). Use
your arms or string to represent the spindle fibers. Describe your results
by completing the following chart.
AA or Aa or
aa?
HH or Hh or
hh?
Which alleles were present in the
original cell?
Which alleles are present in each
daughter cell
produced by mitosis?
Questions on Mitosis
1. Are the chromosomes and genes in the daughter cells produced by
mitosis the same as or different from the chromosomes and genes
in the original cell? Explain why.
2. What would happen if a cell did not make a copy of its DNA (its
chromosomes) before it divided?
3. Why is it important for the chromosomes to line up in the middle of
the cell during mitosis?
4. In a cell which is ready for mitosis, why are the two chromatids of
each chromosome genetically identical?
5. Are the two homologous chromosomes genetically identical?
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Meiosis -- How Your Body Makes Sperm or Eggs
Mitosis gives rise to almost all the cells in the body. A different type of cell
division called meiosis gives rise to sperm and eggs.
During fertilization the sperm and egg unite to form a single cell called
the zygote which contains chromosomes from both the sperm and egg.
The zygote undergoes mitosis to begin development of the human embryo
which eventually becomes a baby.
Why can't your body use mitosis to make sperm or eggs?
Suppose human sperm and eggs were produced by mitosis. How many
chromosomes would each sperm or egg have? ____
If a sperm of this type fertilized an egg of this type, and both the sperm
and egg contributed all of their chromosomes to a zygote, how many
chromosomes would the resulting zygote have?
_____
In humans, how many chromosomes should a zygote have, so the baby's
body cells will each have a normal set of chromosomes? _____
Obviously, if the body used mitosis to make sperm and eggs, the resultant
zygote would have too many chromosomes to produce a normal baby. To
produce a normal zygote, how many chromosomes should each sperm
and egg have? _____
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To produce the needed number of chromosomes in sperm and eggs,
meiosis reduces the number of chromosomes by half. For example, in
humans each sperm and each egg produced by meiosis has only 23
chromosomes, including one chromosome from each pair of homologous
chromosomes. Therefore, after an egg and sperm are united during
fertilization, the resulting zygote has 23 pairs of homologous
chromosomes, one in each pair from the egg and one from the sperm.
When the zygote undergoes mitosis to begin to form an embryo, each cell
will have the normal number of 46 chromosomes.
Cells that have two copies of each chromosome (i.e. cells that have pairs
of homologous chromosomes) are called diploid cells. Most of the cells
in our bodies are diploid cells. Cells that only have one copy of every
chromosome are called haploid cells. Which types of cells in our bodies
are haploid?
Before meiosis, the cell makes a copy of the DNA in each chromosome.
Then, during meiosis there are two cell divisions, meiosis I and meiosis
II. This reduces the chromosome number by half and produces four
haploid daughter cells.
Meiosis I
Meiosis I is different from mitosis because homologous chromosomes line
up next to each of other and then separate, as shown below. This
produces daughter cells with half as many chromosomes as the parent
cell, i.e. haploid cells. Notice that each of the daughter cells has a
different chromosome from the homologous pair of chromosomes. This
means that the alleles in each daughter cell are different.
Cell
18
Cell
Cell
Meiosis II
Meiosis II is like mitosis. The sister chromatids of each chromosome are
separated, so each daughter cell gets one copy of each chromosome in
the mother cell.
Cell
Cell
Cell
Cell
Cell
In the diagram above, label the cells which would be the sperm or eggs
produced by meiosis.
Using one pair of sockosomes, go through each step of meiosis until you
are confident that you understand the difference between Meiosis I and
Mitosis and the difference between Meiosis I and Meiosis II. For example,
what is the difference in the way the pair of homologous chromosomes is
lined up in a cell at the beginning of Meiosis I vs. at the beginning of
Mitosis?
Now, use your group’s sockosomes to model meiosis in a cell which has
two pairs of homologous chromosomes. Find two sockosomes that have
the two different alleles for the gene for albinism (A for pigmented skin and
a for albinism). Next, find two sockosomes that have the two different
alleles for the gene for thumb bending (H for straight thumb and h for the
hitchhiker’s thumb). Put these four sockosomes in a pile to represent the
two pairs of homologous chromosomes, each with the DNA copied so the
cell is ready to undergo meiosis. The genetic makeup of this cell is
AaHh. Now, use these sockosomes to model the steps in meiosis. Begin
by lining up the sockosomes the way real chromosomes line up at the
19
Cell
beginning of Meiosis 1. Notice that there is more than one possible way
for the sockosomes to line up at the beginning of Meiosis 1. As a result,
you can get different combinations of alleles in individual sperm or eggs.
List all of the different possible combinations of alleles in the sperm or
eggs that can be produced by meiosis.
Questions
1. Describe the differences between the mother cell that undergoes
meiosis and the daughter cells produced by meiosis.
2. Describe the differences between daughter cells produced by meiosis
and daughter cells produced by mitosis.
3. The following diagram provides an overview of the information covered
thus far. Review the diagram, and fill in the correct number of
chromosomes per human cell in each blank.
Mother _____
Father _____
↓
↓
Meiosis
egg _____
Meiosis
sperm _____
Fertilization
zygote _____
↓
Mitosis
Embryo _____
↓
Mitosis
baby _____
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Analyzing Meiosis and Fertilization to Understand Genetics
In this section you will investigate how events during meiosis and
fertilization determine the genetic makeup of the zygote, which in turn
determines the genetic makeup of the baby that develops from the zygote.
You already know that sisters or brothers can have different
characteristics, even when they have the same parents. One major
reason for these different characteristics is that the processes of meiosis
and fertilization result in a different combination of alleles in each child.
To begin to understand this genetic variability, you will model meiosis and
fertilization for a very simplified case where there is only one pair of
homologous chromosomes per cell, and the two homologous
chromosomes carry different alleles of the same genes. One person in
your group will be the mother and another will be the father, with
sockosomes as shown below. (Alternatively, you may have four
sockosomes similar to those shown, but labeled h and H).
A
a
Mother
A
a
Father
In this simple example, how many different types of eggs will be produced
by meiosis? _____
How many different types of sperm will be produced by meiosis? _____
The different types of sperm can fertilize the different types of egg to result
in zygotes with different combinations of chromosomes from the mother
and the father. Fertilization can be demonstrated by having the mother
and father each contribute one chromatid from one of their sockosomes to
form a zygote. Thus, the zygote will have a pair of homologous
chromosomes including one chromosome from the egg and one
chromosome from the sperm. Try to produce as many different types of
zygotes as you can by pairing each type of sperm with each type of egg.
To demonstrate fertilization, it works best to lay the chromosomes out on
the table, so you can more easily see the multiple different possible
combinations.
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How many different types of zygotes can be produced by fertilization in
this simple case?
What different combinations of the labeled alleles can be observed in the
zygotes?
A pair of human parents could produce a great many more different
genetic combinations than observed in this simplified example. For
example, humans have 23 pairs of homologous chromosomes, so many,
many different combinations of chromosomes can be found in the eggs or
sperm produced by one person, and the different combinations of eggs
from one mother and sperm from one father could produce zygotes with
approximately 70 trillion different combinations of chromosomes! You can
see why no two people are genetically alike, except for identical twins who
are derived from the same zygote.
Questions
1. How many chromosomes are there in a human skin cell produced by
mitosis?
________
How many chromosomes are there in a human sperm cell produced by
meiosis?
_______
2. Describe the differences between mitosis and meiosis.
3. What are the similarities between mitosis and meiosis?
22
Down Syndrome
Sometimes, meiosis does not happen perfectly, so the chromosomes are
not divided completely equally between the daughter cells produced by
meiosis. For example, an egg or a sperm may receive two copies of the
same chromosome.
If a human egg receives an extra copy of a chromosome, and this egg is
fertilized by a normal sperm, how many copies of this chromosome would
there be in the resulting in zygote?
How many copies of this chromosome would there be in each cell in the
resulting embryo?
When a cell has three copies of a chromosome, the extra copies of the
genes on this chromosome result in abnormal cell function and abnormal
embryonic development. Therefore, in most cases, a zygote which has an
extra chromosome will die early in embryonic development, resulting in a
miscarriage.
However, some babies are born with an extra copy of a small
chromosome (chromosome 21), and this results in the condition known as
Down Syndrome. A karyotype of a boy with Down Syndrome is shown
below.3 Multiple abnormalities result from the extra copy of chromosome
21 in each cell, including mental retardation, a broad flat face, a big
tongue, short height, and congenital heart disease.
3
In this karyotype it is difficult to see the sister chromatids in each chromosome, since they are
very close to each other.
23
24
Mitosis/Meiosis
Directions: Complete the concept map comparing mitosis and meiosis. Use these
words or phrases one or more times: diploid cell, cell division, four haploid cells,
original cell, two cell divisions, body cells, same, chromosomes, gameteproducing cells, half, two diploid cells.
Mitosis
Meiosis
begins with a
begins with a
occurs in
occurs in
consists of
consists of
forming
forming
having the
having
number of
the number of
as the
as the
original cell
25
Mitosis/Meiosis
Directions: Complete the concept map comparing mitosis and meiosis. Use these
words or phrases one or more times: diploid cell, cell division, four haploid cells,
original cell, two cell divisions, body cells, same, chromosomes, gameteproducing cells, half, two diploid cells.
Mitosis
Meiosis
begins with a
begins with a
Diploid
Diploid
occurs in
occurs in
Body Cell
(Somatic Cell)
Gamete
Producing Cells
consists of
consists of
One Cell
Division
Two Cell
Diviosns
forming
forming
2 diploid cells
4 haploid cells
having the
having
SAME
HALF
number of
the number of
Chromosomes
Chromosomes
as the
as the
Original Cell
Original cell
26
Chromosome Number Worksheet
An organism has body cells with 42 chromosomes. Use this information to
answer #1-7
1. A body cell prepares for cell division. How many chromosomes does it have
at the beginning of prophase?__________
2. After the membrane pinches in half, how many chromosomes does each
daughter cell have?___________
3. How many chromosomes did each of the sex cells have that formed this
individual organism?____________
4. how many chromosomes does the egg cell of this organism have?__________
5. How many chromosomes does the body cells have during
interphase?_________
6. What is the diploid number of this organism?__________
7. What is the haploid number of for this organism?___________
8. An organism has 12 chromosomes in its sperm cells. How many
chromosomes does it have in its body cells?
9. An organism has 29 chromosomes in its egg cells. How many chromosomes
does it have in its body cells?
10. An organism has 22 chromosomes in its body cells. How many chromosomes
does it have in its sperm cells?
An organism has body cells with 22 chromosomes. Use this information to
answer #11-17
11. A body cell prepares for cell division. How many chromosomes does it have
at the beginning of prophase?__________
12. After the membrane pinches in half, how many chromosomes does each
daughter cell have?__________
13. How many chromosomes did each of the sex cells have that formed this
individual organism?__________
14. How many chromosomes does the egg cell of this organism have?_______
15. How many chromosomes does the body cells have during interphase?_______
16. What is the diploid number of this organism?_________
17. What is the haploid number for this organism?__________
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An organism has body cells with 78 chromosomes. Use this information to
answer questions #18-24
18. A body cell prepares for cell division. How many chromosomes does it have
at the beginning of prophase?____________
19. After the membrane pinches in half, how many chromosomes does each
daughter cell have?________
20. How many chromosomes did each of the sex cells have that formed this
individual organisms?___________________
21. How many chromosomes does the egg cell or this organism have?_________
22. How many chromosomes does the body cells have during
interphase?_________
23. What is the diploid number of this organism?________
24. What is the haploid number for this organism?_______
An organism has body cells with 46 chromosomes. Use this information to
answer #25-31
25. A body cell prepares for cell division. How many chromosomes does it have
at the beginning of prophase?________
26. After the membrane pinches in half, how many chromosomes does each
daughter cell have?___________
27. How many chromosomes did each of the sex cells have that formed this
individual organism?_________
28. How many chromosomes does the egg cell or this organism have?_________
29. How many chromosomes does the body cells have during
interphase?_________
30. What is the diploid number of this organism?________
31. What is the haploid number for this organism?_______
An organism has body cells with 8 chromosomes. Use this information to
answer #32-38
32. A body cell prepares for cell division. How many chromosomes does it have
at the beginning of prophase?________
33. After the membrane pinches in half, how many chromosomes does each
daughter cell have?___________
34. How many chromosomes did each of the sex cells have that formed this
individual organism?_________
35. How many chromosomes does the egg cell or this organism have?_________
36. How many chromosomes does the body cells have during
interphase?_________
37. What is the diploid number of this organism?________
38. What is the haploid number for this organism?_______
28