Cellular Reproduction

Front 1

Chromosomes form and each chromosome pairs with its homologous chromosome; called a tetrad – four chromatids
In a tetrad, homologous chromosomes can exchange portions of their chromatids; called crossing-over
Occurs at the chiasma
Creates recombinant chromatids (“recombined”)
Provides genetic variation – that’s how each one of us is very different from the other
Sexual reproduction creates genetic variation

Back 1

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Front 2

Tetrads line up in the middle, equatorial plane, of the cell

Back 2

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Front 3

Homologous chromosomes separate and move away from each other to opposite poles of the cell
Each is genetically different from the original cell due to crossing-over

Back 3

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Front 4

Nuclear envelope forms
Cytokinesis occurs resulting in two daughter cells
Daughter cells are NOT identical due to crossing-over in prophase I

Back 4

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Front 5

Chromosomes form
Nuclear envelope disappears

Back 5

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Front 6

Chromosomes line up in the middle of the cell at the equatorial plate

Back 6

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Front 7

Nuclear envelope forms
Cytokinesis occurs resulting in four genetically different gametes

Back 7

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