如图为某二倍体动物精巢内的细胞,字母表示染色体上所携带的基因,下列推断错误的是( )
A:若该细胞为精原细胞,则该生物性别决定方式为XY型
B:若该细胞为精原细胞,则精巢内精细胞的基因型有2种
C:若该细胞为精细胞,则与该细胞同时产生的配子都不正常
D:若该细胞为精细胞,则该生物正常体细胞染色体数目最多时为12条
实验室常用如图所示装置来研究气体的制取和性质,回答下列问题:(1)写出仪器的名称:①____②____。A装置中长颈漏斗下端管口伸入液面下的目的是____。(2)用高锰酸钾制取氧气的化学方程式为____,利用该反应制取氧气,可选用的发生装置是____ (填字母,下同),若选用C装置收集氧气,实验结束后的操作顺序是先将____ ,然后____ ,以防止水倒吸进入热的试管中,造成试管的破裂。(3)在己学过的初中化学知识里,利用A装置可以制取二氧化碳,实验室常用石灰石与稀盐酸制取该气体,化学方程式为____ ,基本反应类型是____ ,收集二氧化碳应选用____ 装置。(4)NO气体难溶于水,易被空气氧化,收集NO气体能选用的装置是____ 。
近来雾霾频现,“PM2.5”数据监测纳入公众视野.“PM2.5”是指大气中直径小于或等于2.5微米的细小颗粒物,也称为可入肺颗粒物.下列有关说法中,错误的是( )
阅读下面图表,从每小题所给的A、B、C、D四个选项中选出一个最佳选项。
There will be three kids movies in theaters. Let's know the main idea of them first.
The Snow Queen
The Snow Queen tells the story of the Snow Queen who covered the world in ice, setting out to destroy (破坏) everything, including the family of the glassmaker Vegard. Luckily, Vegard and his wife were able to save their daughter Gerda and their son Kai before it was too late. But when Kai was discovered by the Snow Queen's servant (仆人), Gerda took a journey across the icy wonderland, facing difficulties and finding new friends to set Kai free, to beat the Snow Queen and warm the hearts of people everywhere.
Angels Sing
As a child, Michael Walker wished every day could be Christmas. That continued, until a tragic accident broke down his holiday spirit. Thirty years later, Michael still can't feel any joy for Christmas, though encouragement comes from his playful wife (Connie Britton) and kind parents (Kris Kristofferson and Fionnula Flanagan). But when his young son (Chandler Canterbury) face a tragedy (悲剧), Michael needs to make amends (赔偿) with his past. A mysterious man named Nick (Millie Nelson) gives Michael a gift that can give him the courage to find the Christmas joy that he lost.
Adventures of the Penguin King
Rex, a young King Penguin, has been away from his home for three years, learning to hunt in the wild oceans, but now he's back in Penguin City. His task: to find a wife, settle down and raise a chick. But can he survive in the bad conditions on an island at the bottom of the world?
“庄稼一枝花,全靠肥当家”.植物生长过程中需要最多的无机盐是( )
氯气是一种重要的化工原料.如图为实验室制取氯气的装置.请回答: