A:猫捉老鼠
B:鱼用鳃呼吸
C:公鸡报晓
D:壁虎趴在墙上一动不动
如图甲是H2O2酶活性受pH影响的曲线,图乙表示在最适温度下,pH=b时H2O2分解产生的O2量随时间的变化.若该酶促反应过程中改变某一初始条件,以下改变正确的是( )
根据短文内容,完成下列各小题。
It's four thirty in the afternoon. There are many students on the playground. Jim and his friends are playing basketball. Li Lei and other boys are playing football. Miss Gao is watching the games. She is looking after the clothes, too. Where are the girls? They are over there. Some are running, others are jumping. The twins are on duty today. They are in the classroom. Lucy is cleaning the window, Lily is sweeping the floor. They are working hard. They are tired(疲倦的) but happy.
如图是植物细胞和动物细胞的立体结构模式图,下列说法正确的是( )
下列有关生命的物质基础和结构基础的阐述,错误的是( )
①C、H、O、N、P、S是蛋白质、ATP、染色质、核苷酸共有的化学元素;
②葡萄糖是细胞新陈代谢所需能量的直接来源;
③乳酸菌、酵母菌和蓝藻的细胞内都有核糖体、DNA、RNA;
④线粒体可在有氧条件下将葡萄糖氧化分解为CO2和水;
⑤糖蛋白、抗体、受体、限制性内切酶都是具有特异性识别作用的物质;
⑥胆固醇是构成动物细胞膜的重要成分,还参与血液中脂质的运输.