挤牛奶的女工常与患牛痘的奶牛接触，她们的手上会出现牛痘脓疱，

挤牛奶的女工常与患牛痘的奶牛接触，她们的手上会出现牛痘脓疱，但在天花流行时，却从不感染天花。与这种免疫力的产生关系最密切的细胞器是

A线粒体 B中心体 C溶酶体 D核糖体

答案

相关题目

下图示意某地的沉积岩层与火成岩体的相互关系。则各岩层

下图示意某地的沉积岩层与火成岩体的相互关系。则各岩层、岩体的生成时代按由老至新的顺序依次是（） A．火成岩1、沉积岩1、沉积岩2、火成

目前，广州市重点发展的工业是（） A.原材料工业和装

目前，广州市重点发展的工业是（） A.原材料工业和装备制造业 B.电子、通信 C.轻纺、化工

Ralph and Norton can grow to be 40 feet long and live in a tank as large as a fo

Ralph and Norton can grow to be 40 feet long and live in a tank as large as a football field. What are they? They’re the only two whale sharks at a North American aquarium （水族馆） You can

Her brother was _______ by the army because of his bad eyesight. A. promoted

Her brother was _______ by the army because of his bad eyesight. A. promoted B. accepted C. rejected D. served

根据短文内容判断正(T)误(F) A man and

根据短文内容判断正(T)误(F) A man and his cat A man has a cat. He likes her very much. At meal time the cat sits at the table with him. The man eats wit

下列说法正确的是（） A．缺乏维生素A会引起坏血病 B．缺

下列说法正确的是（） A．缺乏维生素A会引起坏血病 B．缺铁会引起甲状腺肿 C．大米富含糖类 D．蔬菜中含大量蛋白质

一曲凄怆的《松花江上》当年曾传唱大江南北，唱出了东北

一曲凄怆的《松花江上》当年曾传唱大江南北，唱出了东北人民流离失所、家破人亡的悲痛之情。它所反映的东北人民的苦难历史始于 A.九一八事变 �

It doesn’t look like rain, so you _____ bring your umbrella with you. A

It doesn’t look like rain, so you _____ bring your umbrella with you. A .mustn’t B .can’t C .may not D .needn’t

挤牛奶的女工常与患牛痘的奶牛接触，她们的手上会出现牛痘脓疱，

答案

相关题目

最新题目