2011年2月21日,卫生部、国家工商总局、国家粮食局等7个部门发出公告,自2011年5月1日起,禁止在面粉中添加过氧化苯甲酰、过氧化钙。过氧化苯甲酰是面粉增白剂,可以改变面粉外观,却能破坏面粉中叶酸等微量营养素,增加人的肝脏负担。过氧化苯甲酰的分子式为C14H10O4 。下列关于过氧化苯甲酰的说法错误的是 ( )
A:过氧比苯甲酰由三种元素组成
B:过氧化苯甲酰属于有机化合物
C:过氧化苯甲酰的相对分子质量是242
D:过氧化苯甲酰中含有14个碳原子、10个氢原子和4个氧原子
许多遗传实验表明,一般的环境条件的变化不易使基因发生改变,但容易使生物的表现型发生改变.因此,生物的表现型是____和____共同作用的结果.
下列各句中,没有语病的一句是( )
完形填空
I have a good friend. His name is Tom. He is a nice boy, but he eats too1 and doesn't like sports. He has a big2 every morning. He has four eggs, 3 of bread and butter and 4 big glass of milk for it. 5 lunch, he eats two hamburgers, a lot of French fries of chicken. He 6 a lot of cola or soda, too. For dinner, he likes beef and salad. He7 eats beef, chicken, hamburgers, and eggs. He likes ice cream, cola and soda, 8. Too much food is not 9 for health. So Tom is very 10.