Which of the following occurs during the preimplantation period, i.e. the first week of development?
A. Formation of the notochord
B. Formation of the bilaminar disc
C. Formation of the first branchial arch
D. Formation of the blastocyst
E. Formation of the forebrain

In which of the following weeks of embryonic development does the odontogenic epithelium first appear in the maxillary and mandibular processes.
A. Week 2
B. Week 3
C. Week 4
D. Week 5
E. Week 6

Which of the following best describes the neural groove?
A. A segmented series of eight bulges corresponding with the hindbrain.
B. A narrow groove on the caudal/posterior surface of the trilaminar embryo that finishes in a small depression called the primitive node.
C. A midline depression on the dorsal surface of the trilaminar embryo that is defined by the raised margins of the neural folds.
D. Mesodermal thickenings adjacent to the notochord that form segmented blocks.
E. A thickening of ectodermal tissue on the rostral/anterior surface of the bilaminar embryo.

The bilaminar embryonic disk consists of which of the following tissue layers?
A. Epiblast and Mesoderm
B. Epiblast and Trophoblast
C. Mesoderm and Hypoblast
D. Mesoderm and Trophoblast
E. Epiblast and Hypoblast