Question

Rapid “horsetail motion” is visible when S. pombe enters this stage in response to starvation. During this phase, an unknown interference mechanism maintains a uniform spacing between assembly sites for members of the ZMM family and SPO11. Exit from this stage is preceded by a fourfold increase in cell diameter and the breakdown of the germinal vesicle. Cells in this stage are extremely radiosensitive and will be eradicated by half a gray. The activation of EGF receptors on cumulus cells causes adjacent cells to exit this stage, whose five substages (10[1]-5[1])are largely named for their thread-like chromosomes. A pulse of (10[1])LH triggers oocytes (“OH-uh-cytes”) to exit the (-5[1])diplotene (“DIP-luh-teen”) portion of this stage, (-5[1])where they have been arrested (-5[1])since before (-5[1])birth. (10[1]-5[1])For 10 points, (-5[1])name this (10[1])cellular stage when crossing-over occurs, (10[2])the (-5[1])very first (0[1])stage (10[1])of meiosis. ■END■ (10[12]0[1])

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