Chapter 11 Section 4 Meiosis:
Chromosomes: strands of ____________________inside the cell nucleus, are ______________________
Genes: are located in _____________________________on chromosomes. An organism must inherit a
______________________________ of every gene from each of its “parents.”
Gametes when the _______________________ of genes in an organism are___________________________.
The male gamete in animals is the________________!!! In higher plants it is___________________!!!!
The female gamete in animals is the ______________________.In higher plants it is__________________!!!
Chromosome Number: All organisms have ______________________________________of chromosomes.
Diploid: cell that contains __________________________of____________________________________. The
number of chromosomes in a diploid cell = ___________.
A body cell of a human has ________________________and are DIPLOID.
____N = _________
Haploid cells: contain only a ________________________of chromosomes, and a single set of___________.
Gametes of ________________________reproducing organisms are___________________________.
Remember: Haploid = ________________the chromosome number
Haploid cells are represented by the______________________.
Our gametes (egg/sperm) have _________________________and are HAPLOID
N = _______
Meiosis: is a ____________________division. The number of chromosomes per cell is __________________
as homologous chromosomes separate from a diploid cell.
Meiosis involves________________________, meiosis I (__________1) and meiosis II. (_________________2)
By the end of meiosis II, the diploid cell that entered meiosis has become ____ _______________ ________.
MEIOSIS 1:
Crossing over: when homologous chromosomes form tetrads & __________________of their ____________
in MEIOSIS 1  THIS produces ______________________of alleles – genes which is why we don’t look alike
Tetrad: when chromosomes ______ with their homologous chromosome. There are _____________in tetrad.
MEIOSIS II :
Comparing Mitosis and Meiosis: Mitosis results in the production of_________________________________________.
Meiosis produces _______________________________________________________.
Chapter 11 Section 4 Meiosis:
Chromosomes: strands of DNA and protein inside the cell nucleus—are the carriers of genes.
Genes: are located in specific positions on chromosomes. An organism must inherit a single copy of every
gene from each of its “parents.”
Gametes when the two sets of genes in an organism is separated into one set.
The male gamete in animals is the Sperm!!! In higher plants it is pollen!!!!
The female gamete in animals is the Egg or Ova In higher plants it is Seed or ovule!!!!
Chromosome Number: All organisms have different numbers of chromosomes.
Diploid: cell that contains both sets of homologous chromosomes. The number of chromosomes in a diploid
cell = 2N.
A body cell of a human has 46 chromosomes and are DIPLOID.
2N = 46
Haploid cells: contain only a single set of chromosomes, and a single set of genes.
Gametes of sexually reproducing organisms are haploid.
Remember: Haploid = Half the chromosome number
Haploid cells are represented by the symbol N.
Our gametes (egg/sperm) have 23 chromosomes and are HAPLOID
N = 23
Meiosis is a reduction division. The number of chromosomes per cell is cut in half as homologous
chromosomes separate from a diploid cell.
Meiosis involves two divisions, meiosis I and meiosis II.
By the end of meiosis II, the diploid cell that entered meiosis has become 4 haploid cells.
MEIOSIS 1:
Crossing over: when homologous chromosomes form tetrads and exchange portions of their chromatids in
MEIOSIS 1  THIS produces new combinations of alleles – genes which is why we don’t all look alike!!!!!
Tetrad: when each chromosome pairs with its homologous chromosome There are 4 chromatids in a tetrad.
MEIOSIS II :
Comparing Mitosis and Meiosis
Mitosis results in the production of two genetically identical diploid cells. Meiosis produces four genetically different
haploid cells
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Comparing Mitosis and Meiosis
Comparing Mitosis and Meiosis
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If the body cells of humans contain 46 chromosomes, a single sperm cell should have
46 chromosomes.
23 chromosomes.
92 chromosomes.
between 23 and 46 chromosomes.
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During meiosis, the number of chromosomes per cell is cut in half through the separation of
daughter cells.
homologous chromosomes.
gametes.
chromatids.
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The formation of a tetrad occurs during
anaphase I.
metaphase II.
prophase I.
prophase II.
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In many female animals, meiosis results in the production of
only 1 egg.
1 egg and 3 polar bodies.
4 eggs.
1 egg and 2 polar bodies.
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Compared to egg cells formed during meiosis, daughter cells formed during mitosis are
genetically different, while eggs are genetically identical.
genetically different, just as egg cells are.
genetically identical, just as egg cells are.
genetically identical, while egg cells are genetically different.