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La biología del desarrollo prenatal


Introducción


THE BIOLOGY OF PRENATAL DEVELOPMENT

.English


 

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Capítulo 1   Introducción

Reproducir película - The Dynamic Process
Reproducir película
The dynamic process by which the single-cell human zygote becomes a 100-trillion-cell adult is perhaps the most remarkable phenomenon in all of nature.

Reproducir película - Routine Functions
Reproducir película
Researchers now know that many of the routine functions performed by the adult body become established during pregnancy - often long before birth.

Reproducir película - The Developmental Period
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The developmental period before birth is increasingly understood as a time of preparation during which the developing human acquires the many structures, and practices the many skills, needed for survival after birth.

Capítulo 2   Terminología

Pregnancy in humans normally lasts approximately 38 weeks as measured from the time of fertilization, or conception, until birth.

Reproducir película - The Embryonic Period
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During the first 8 weeks following fertilization, the developing human is called an embryo, which means "growing within." This time, called the embryonic period, is characterized by the formation of most major body systems.

Reproducir película - The Fetal Period
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From the completion of 8 weeks until the end of pregnancy, "the developing human is called a fetus," which means "unborn offspring." During this time, called the fetal period, the body grows larger and its systems begin to function.

Reproducir película - Size Comparison
Reproducir película
All embryonic and fetal ages in this program refer to the time since fertilization.
Introducción