This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: 2/9/12 NAME: ______________________________ Bio126, Midterm WRITE YOUR NAME ON EVERY PAGE I. Multiple Choices 1. The three main layers in the early embryonic stage of brain development are the a. ectoplasm, endoplasm, and mesoplasm. b. ectoderm, endoderm, and mesoderm. c. gastrula, blastula, and notochord d. ectoderm, ectoplasm, and notochord e. inner, outer, and middle. 2. Which of the following statements about mutations of Sonic hedgehog and related genes is false ? a. They cause approximately 30 percent of stillbirths. b. They often result in a cyclopean (single) eye. c. They can lead to holoprosencephaly. d. They can transform granule cells, leading to medulloblastoma. e. They can transform basal epidermal cells, leading to basal cell carcinoma. 3. Which of the following does not play an important role in the establishment of axon tracts and in growth cone navigation? a. Cell adhesion molecules b. Extracellular matrix components c. Cytoskeletal proteins d. Synaptic vesicle proteins e. Second messenger systems 4. Neurotrophic factors a. ensure that the correct numbers of axons innervate each target cell....
View Full Document
- Winter '09
- Neural tube, Schwann Cell, d. ectoderm