[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"kakomon-q-2025-ippan-13":3},{"slug":4,"exam_year":5,"exam_round":6,"section":7,"section_code":8,"number":9,"body":10,"choices":11,"correct_indices":28,"explanation":29,"has_explanation":24,"tags":30},"2025-ippan-13",2025,3,"一般","ippan",13,"眼球で水晶体（レンズ）の厚さを調節するのはどれか。",[12,16,19,21,25],{"index":13,"body":14,"is_correct":15},1,"角膜",false,{"index":17,"body":18,"is_correct":15},2,"虹彩",{"index":6,"body":20,"is_correct":15},"硝子体",{"index":22,"body":23,"is_correct":24},4,"毛様体",true,{"index":26,"body":27,"is_correct":15},5,"網膜",[22],"正答は4（毛様体）。毛様体（毛様体筋）が収縮・弛緩することでチン小帯の張力が変わり、水晶体（レンズ）の厚みを変えてピントを合わせる（遠近調節）。1角膜は光を屈折させるが厚さは調節しない、2虹彩は瞳孔径を変えて光量を調節する、3硝子体は眼球内を満たすゼリー状組織、5網膜は光を受容する。いずれもレンズの厚さ調節はしない。**覚え方**: ピント調節＝毛様体、光量調節＝虹彩（瞳孔）。",null]