观察人的口腔上皮细胞是初中《生理卫生》课中的一个基本实验。如将本实验内容适当扩展,增设鉴定人类性别一项,可在不增加器材、药品、步骤情况下,不仅能达到预期的实验目的,而且还能激发学生学习兴趣,开阔学生视野,培养学生观察思考问题能力。该实验设计如下: (原理)正常女性的二条性染色体XX,在间期细胞核中,其中一条X染色体失活,呈浓缩状态称为X染色质,一般位于核膜内侧边缘,呈三角形。正常男性只有一条X染色体, Observing human oral epithelial cells is a basic experiment in junior high school “physiological health” class. If the content of this experiment is properly expanded, adding an item for identifying the human gender can not only achieve the intended experimental purpose without increasing equipment, drugs, and steps, but also stimulate students’ interest in learning, broaden their horizons, and develop students’ observations. Ability to think about problems. The experiment was designed as follows: (Principle) Two sex chromosomes XX of normal females. In the interphase nucleus, one of the X chromosomes is inactivated, and the condensed state is called X chromatin, which is generally located at the inner edge of the nuclear membrane and is triangular. Normal males have only one X chromosome,