Quiz Response

Closure of the neural tube occurs around day 26 of embryonic life.

As the neural tube forms, the closing process is critical, occurring from the cranial to the caudal end as the anterior neuropore closes around day 24, the posterior around day 26. This is a critical event, as defects in closure may result in spina bifida or other neural tube defects. The risk of a neural tube defect can be decreased by folic acid supplements.

Embryology Resources

A day by day and week by week review of embryological terms with graphical representations from the University of Pennsylvania.

Another one from the University of Cincinnati College of Medicine. In order to play the animations, you need to save them to your computer.

Attention Year 1 and 2 Students

A 25-year-old female presents to her obstetrician after taking a home pregnancy test with a positive result. She states that twins run in her family and would like an ultrasound to determine if she has a twin pregnancy. Splitting of the embryo at the blastocyst stage results in which of the following?

A. Conjoined twins
B. Dizygotic twins
C. Fraternal twins
D. Monozygotic twins
E. Single gestation

Post your answers here. I will post correct answer on Friday.