DEP 2004 Lecture Notes - Lecture 10: Neural Tube Defect, Spina Bifida, Prenatal Development
17 Feb 2017
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Each egg and each sperm contain 23 chromosomes. Genetically male, but may grow up looking female. Must have a y chromosome in order to have male characteristics. Nature vs. nurture vs. nature and nurture . Family resemblance is insufficient to claim heritability. Sperm (23 chromosomes) + egg (23 chromosomes) All body systems appear and come online . We are born with 99% of neurons we will ever have, and develop the rest throughout our life. Means that the head is the first to develop, body has to catch up (why babies are born with big heads that are unproportional to their body) Third week: head is 50% body length. Fourth week: neural tube begins to close. Teratogens: anything that interferes with prenatal development (defects) Declines attributed to early detection, improved nutrition, reduced teratogen risk. Thalidomide, psychoactive drugs, tobacco, alcohol, drugs of abuse (heroin, cocaine, etc)
