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高中《生物》第203页“观察果蝇唾腺细胞的巨大染色体”的实验,可用摇蚊幼虫(即市售喂鱼的红虫)为实验材料,不仅可以达到实验目的,而且具有取材方便,便于操作和能避免因果蝇培养所需时间而与教学进度很难合拍等优点。做法如下: 一、解剖幼虫:将幼虫放在载片中央的0.7％生理盐水中,用两支解剖针把虫体前1/3处切断,弃去后2/3。再用针按住幼虫头部,用另一针从头后向后将内脏挤出。从挤出的内脏中可找到两个长约2mm左右,形似两指棉手套的无色透明的唾腺。
High school “Biology” on page 203 “observe the giant chromosome of the fruit fly salivary gland cells” experiment, can be used Chironomidae larvae (ie commercially available fish, red worms) as the experimental material, not only can achieve experimental purposes, but also has convenient materials, easy The operation and the ability to avoid the time required for the cultivation of fruit flies and the difficulty of coordinating with the teaching progress are advantages. The procedure is as follows: 1. Dissect the larvae: Place the larvae in 0.7% saline in the center of the slide, cut off the anterior 1/3 of the worm body with two dissection needles, and discard 2/3 of the larvae. Then hold the larvae’s head with a needle and squeeze the viscus back and forth from the back with another needle. From the extruded viscera, two colorless and transparent salivary glands about 2 mm long and shaped like two-fingered cotton gloves can be found.