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 are largely named for their thread-like chromosomes. A pulse of LH triggers oocytes (“OH-uh-cytes”) to exit the diplotene (“DIP-luh-teen”) portion of this stage, where they have been arrested since before birth. For 10 points, name this cellular stage when crossing-over occurs, the very first stage of meiosis. ■END■
ANSWER: prophase I [accept diplotene, diplonema, or dictyate until “diplotene” is read; prompt on meiotic prophase; prompt on meiosis or meiotic until “meiosis” is read; reject “mitosis” or “M phase”]
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= Average correct buzz position