Download Meiosis II

Interest Grabber
Section 11-4
How Many Chromosomes?
Normal human body cells each contain 46 chromosomes. The cell division
process that body cells undergo is called mitosis and produces daughter
cells that are virtually identical to the parent cell. Working with a partner,
discuss and answer the questions that follow.
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Section:
Interest Grabber continued
Section 11-4
1. How many chromosomes would a sperm or an egg contain if either one
resulted from the process of mitosis?
2. If a sperm containing 46 chromosomes fused with an egg containing 46
chromosomes, how many chromosomes would the resulting fertilized
egg contain? Do you think this would create any problems in the
developing embryo?
3. In order to produce a fertilized egg with the appropriate number of
chromosomes (46), how many chromosomes should each sperm and
egg have?
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Section:
Section Outline
Section 11-4
11–4
Meiosis
A. Chromosome Number
B. Phases of Meiosis
1. Meiosis I
2. Meiosis II
C. Gamete Formation
D. Comparing Mitosis and Meiosis
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Section:
Crossing-Over
Section 11-4
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Section:
Crossing-Over
Section 11-4
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Section:
Crossing-Over
Section 11-4
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Section:
Figure 11-15 Meiosis
Section 11-4
Meiosis I
Interphase I
Prophase I
Metaphase I
Anaphase I
Cells undergo a round of
DNA replication, forming
duplicate Chromosomes.
Each chromosome pairs with
its corresponding
homologous chromosome to
form a tetrad.
Spindle fibers attach to the
chromosomes.
The fibers pull the
homologous chromosomes
toward the opposite ends of
the cell.
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Section:
Figure 11-15 Meiosis
Section 11-4
Meiosis I
Interphase I
Prophase I
Metaphase I
Anaphase I
Cells undergo a round of
DNA replication, forming
duplicate Chromosomes.
Each chromosome pairs with
its corresponding
homologous chromosome to
form a tetrad.
Spindle fibers attach to the
chromosomes.
The fibers pull the
homologous chromosomes
toward the opposite ends of
the cell.
Go to
Section:
Figure 11-15 Meiosis
Section 11-4
Meiosis I
Interphase I
Prophase I
Metaphase I
Anaphase I
Cells undergo a round of
DNA replication, forming
duplicate Chromosomes.
Each chromosome pairs with
its corresponding
homologous chromosome to
form a tetrad.
Spindle fibers attach to the
chromosomes.
The fibers pull the
homologous chromosomes
toward the opposite ends of
the cell.
Go to
Section:
Figure 11-15 Meiosis
Section 11-4
Meiosis I
Interphase I
Prophase I
Metaphase I
Anaphase I
Cells undergo a round of
DNA replication, forming
duplicate Chromosomes.
Each chromosome pairs with
its corresponding
homologous chromosome to
form a tetrad.
Spindle fibers attach to the
chromosomes.
The fibers pull the
homologous chromosomes
toward the opposite ends of
the cell.
Go to
Section:
Figure 11-17 Meiosis II
Section 11-4
Meiosis II
Prophase II
Metaphase II
Anaphase II
Meiosis I results in two
The chromosomes line up in a The sister chromatids
haploid (N) daughter cells,
similar way to the metaphase separate and move toward
each with half the number of stage of mitosis.
opposite ends of the cell.
chromosomes as the original.
Go to
Section:
Telophase II
Meiosis II results in four
haploid (N) daughter cells.
Figure 11-17 Meiosis II
Section 11-4
Meiosis II
Prophase II
Metaphase II
Anaphase II
Meiosis I results in two
The chromosomes line up in a The sister chromatids
haploid (N) daughter cells,
similar way to the metaphase separate and move toward
each with half the number of stage of mitosis.
opposite ends of the cell.
chromosomes as the original.
Go to
Section:
Telophase II
Meiosis II results in four
haploid (N) daughter cells.
Figure 11-17 Meiosis II
Section 11-4
Meiosis II
Prophase II
Metaphase II
Anaphase II
Meiosis I results in two
The chromosomes line up in a The sister chromatids
haploid (N) daughter cells,
similar way to the metaphase separate and move toward
each with half the number of stage of mitosis.
opposite ends of the cell.
chromosomes as the original.
Go to
Section:
Telophase II
Meiosis II results in four
haploid (N) daughter cells.
Figure 11-17 Meiosis II
Section 11-4
Meiosis II
Prophase II
Metaphase II
Anaphase II
Meiosis I results in two
The chromosomes line up in a The sister chromatids
haploid (N) daughter cells,
similar way to the metaphase separate and move toward
each with half the number of stage of mitosis.
opposite ends of the cell.
chromosomes as the original.
Go to
Section:
Telophase II
Meiosis II results in four
haploid (N) daughter cells.
Figure 11-17 Meiosis II
Section 11-4
Meiosis II
Prophase II
Metaphase II
Anaphase II
Meiosis I results in two
The chromosomes line up in a The sister chromatids
haploid (N) daughter cells,
similar way to the metaphase separate and move toward
each with half the number of stage of mitosis.
opposite ends of the cell.
chromosomes as the original.
Go to
Section:
Telophase II
Meiosis II results in four
haploid (N) daughter cells.
Section Outline
Section 11-5
11–5
Linkage and Gene Maps
A. Gene Linkage
B. Gene Maps
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Section:
Comparative Scale of a Gene Map
Section 11-5
Mapping of Earth’s
Features
Mapping of Cells,
Chromosomes, and Genes
Cell
Earth
Country
Chromosome
State
Chromosome
fragment
City
People
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Section:
Gene
Nucleotide
base pairs
Figure 11-19 Gene Map
of the Fruit Fly
Section 11-5
Exact location on chromosomes
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Section:
Chromosome 2