The Cellular Basis of

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Chapter 7

• The Cellular Basis of
• Reproduction and Inheritance

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Genes and Reproduction

• Chromosome DNA containing structures that carry
  the organisms genes
• Asexual Reproduction replicating by cell
  division without transfer of genetic material
• Sexual Reproduction replication requiring
  fertilization of an egg by sperm

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The Cell Cycle
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Mitosis Cell Division
Interphase
Prophase
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Mitosis Cell Division
Metaphase
Anaphase
Telophase and Cytokinesis
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Cytokinesis in Animals
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Cytokinesis in Plants
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Homologous Chromosomes
In cell replication, chromosomes replicate but
initially the sister chromatids stay connected at
the centromere Mitosis replicating the
cell Meiosis halving of chromosome number
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Meiosis Gametogenesis
The products of meiosis are four cells, each with
half the number of chromosomes that were in the
parent cell
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Meiosis Gametogenesis
In meiosis I, homologous chromosomes separate,
reducing genetic information
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Meiosis Gametogenesis
In meiosis II, sister chromatids separate,
halving the chromosome number
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Mitosis vs. Meiosis
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Independent Assortment
Meiosis can result in more than one possible
arrangement of chromosomes in the gametes
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Crossing Over
When homologous chromosomes pair up, they can
stick together and exchange pieces of DNA,
resulting in a new combination of genes
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Non-Disjunction Failure to Split
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Results of Non-Disjunction
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Alterations to Chromosome Structure
Other types of mutations
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Summary

• Cell Reproduction
• Mitosis
• Meiosis
• Mutations