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The Endowment for Human Development
The Endowment for Human Development
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DNA Structure

From The Biology of Prenatal Development.Buy Now

Note:

Each side of the ladder is made from alternating deoxyribose and phosphate molecules.

Label Key:

1. sides of ladder
2. rungs of ladder
All ages referenced to fertilization, not last menstrual period.
Fertilization Begins
Fertilization Begins
Chromosomes
Chromosomes
DNA Structure
DNA Structure
A Human Cell
A Human Cell
Chromosomes and the Nucleus
Chromosomes and the Nucleus
Sperm
Sperm
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