Answer to Question 1
Describe the two most common neural tube defects and what is known about their development.
Answer to Question 2
Proving that environmental contaminants cause reproductive damage is difficult, but evidence in wildlife is established and seems likely for human beings. Infants and young children of pregnant women exposed to environmental contaminants such as lead show signs of delayed mental and psychomotor development. During pregnancy, lead readily crosses into the placenta, inflicting severe damage on the developing fetal nervous system. In addition, infants exposed to even low levels of lead during gestation weigh less at birth and consequently struggle to survive. For these reasons, it is particularly important that pregnant women receive foods and beverages grown and prepared in environments free of contamination.
Mercury is another contaminant of concern. Fatty fish are a good source of omega-3 fatty acids, but some fish contain large amounts of the pollutant mercury, which can impair fetal growth and harm the developing brain and nervous system. Because the benefits of seafood consumption seem to outweigh the risks, pregnant (and lactating) women need reliable information on which fish are safe to eat.
Examples of common forms of strabismus: (A) esotropia with the right eye turning inward and (B) exot
Common Pathogens Associated with Health Care–Associated Infections
Tornado Formation: Nonsupercell Tornado Development
Common Fluoride Products
Fetal Development Timeline
B Cells: Development of Self-Recognition and Self-Tolerance