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Let’s Play!
All of these topics will be on your test tomorrow, so pay attention!
Meiosis: The Steps
Meiosis Vocabulary
Random Chromosome Segregation & Probability
Fertilization
Gender Determinati
on
How much DNA?
200
300
400
500
Meiosis: The Steps
Meiosis Vocabulary
Random chromoso
me segregatio
n & probability
Fertilization
Gender determinatio
n
How much DNA?
100
200
300
400
500
100
200
300
400
500
100
200
300
400
500
100
200
300
400
500
100
200
300
400
500
100
List the steps of meiosis in order
1. Prophase2. Metaphase3. Anaphase4. Telophase
5. Cytokinesis(this then repeats)
During which stage of meiosis does crossing over occur?
Prophase 1
How many cells are produced by the end of
cytokinesis 2?
4
Homologous chromosomes are separated during
this stage of meiosis
Anaphase 1
Sister chromatids are separated
during this phase of meiosis.
Anaphase 2
After replication, these segments of DNA look like the
letter X
chromosome
Somatic cells are 2N, which indicates
two sets of chromosomes.
What word means 2n?
diploid
Gametes are labeled N because they have one set of chromosomes. What word means N?
Haploid
The left and right side of a
chromosome when it looks like an X are
called ______
Sister chromatids
The fusion of two gametes creates a diploid cell called a
______
zygote
The chance that a gamete will have the paternal homologue of a chromosome is
_____%
50
The chance that a gamete will have two paternal homologues is ___% (show your
calculations)
½ x ½ = ¼ ¼ = 25%
Set up and evaluate an expression to
calculate the probability of a
gamete having 5 paternal homologues
½ x ½ x ½ x ½ x ½
1/32
Draw all possible gametes that can be produced from the parent cell below
XXX X
Note: this parent cell has already undergone DNA replication
What is the probability of an
Rh+/Rh- man producing a sperm
cell with a Y chromosome and an
Rh+ gene?
1/8
Fertilization occurs when a sperm cell
and an ovum combine to form
one cell. Sperm and ova are both _____.
gametes
The name of the cell created by the fusion of a sperm cell and an ovum is
a ______.
zygote
DailyDouble!
Not all of the cells created by females during meiosis
are used during fertilization. What are
these cells that are discarded and how many are made from one cell undergoing meiosis?
Polar bodies
After fertilization occurs, the zygote
grows by creating more cells. What process produces these new
cells?
meiosis
By mistake, an ovum has two copies of the 21st
chromosome. How many copies of the 21st
chromosome will the zygote have if the ovum is
fertilized by a normal sperm?
3. This condition results in Down
Syndrome.
Women have ___ copies of the X
chromosome while men have __.
2, 1
What sex chromosome do ova
always contain?
X
Why do sperm determine the
gender of the child?
Sperm can contain an X or a Y
chromosome, which will pair with the X chromosome in the
ovum.
What is the probability of a
couple having two boys?
½ x ½ = ¼ Chance of boy 1
Chance of boy 2
What is the chance of a woman with A/B blood and
a man with A/B blood having a boy with B/B
blood?
1 x ½ x ½ x ½ = 1/8
Chance of X
chromosom
e from w
oman
Chance of y chrom
osome from
man
Chance of B
chromosom
e from w
oman
Chance of B
chromosom
e from w
oman
Parent cells of meiosis have ___
copies of each chromosome. They
are ____ (2N).
2, diploid
After DNA replication, chromosomes look like an X. The cell has __
times as much DNA as it started with.
2
Somatic cells have ___ times as many chromosomes as
gametes.
2
If your somatic cells have 46 chromosomes, how many chromosomes do
your gametes have?
23
DailyDouble!
You discover a new species. It has gametes with 27 chromosomes.
How many chromosomes do you expect to find in its
somatic cells?
54
FinalJeopardy
Mitosis vs Meiosis
Name 3 key differences between mitosis and meiosis.
One of your differences must be a drawing of metaphase
1 in meiosis and metaphase in mitosis.
Mitosis
-Produces 2 somatic cells
(diploid)-Daughter cells
are identical
Meiosis-Produces 4
gametes (haploid)
-Daughter cells are different
from eachother
XXXX
XXXXXXXX
