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6 Cards in this Set
- Front
- Back
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1. The lens placode develops in:
A. surface ectoderm B. neural ectoderm C. neural crest D. mesoderm E. mesenchyme |
A. Neural ectoderm forms the optic cup; mesenchyme is from neural crest and mesoderm
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Q. The optic cup develops from:
A. surface ectoderm B. neural ectoderm C. neural crest D. mesoderm E. mesenchyme |
B
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Q. The neural crest develops from:
A. surface ectoderm B. neural ectoderm C. neural crest D. mesoderm E. mesenchyme |
C, D
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2. The iris sphincter muscle is derived from:
A. the mesoderm of the iris stroma B. the pupillary membrane C. neural ectoderm D. the second wave of mesenchyme E. neural crest |
C. Most muscle tissue is derived from mesenchyme; the iris muscle are unusually in that they are derived from neural ectoderm
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3. When do the ganglion cell axons of the optic nerve begin to show myelin?
A. as they enter the optic stalk to begin growing toward the lateral geniculate nucleus (LGN) B. once they pass through the optic chiasm C. as soon as they exit the ganglion cell D. once they reach the LGN |
D. The ganglion cell axons are unmyelinated until they reach their termination, and then the myelin is laid down around the fibers from the LGN to the lamina cribrosa
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4. The apical surfaces of the fetal nucleus form:
A. the inverted Y-suture B. the upright Y-suture C. stellate sutures D. no sutures are found in the fetal nucleus |
B. This is the anterior suture; the embryonic nucleus has no sutures
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