题目

Leber遗传性视神经是一种遗传病，此病是由线粒体DNA基因突变所致。某女士的母亲患有此病，如果该女士结婚生育，下列预测正确的是 （ ）A. 如果生男孩，孩子不会携带致病基因 B. 如果生女孩，孩子不会携带致病基因C. 不管生男或生女，孩子都会携带致病基因 D. 必须经过基因检测，才能确定 答案：【答案】C【解析】Leber遗传性视神经病是由线粒体DNA基因突变所致，属于细胞质遗传．已知女士的母亲患有Leber，则该女士肯定患有该病，所以当该女士结婚生育时，其子女也必定患病．　　短文改错 　　On July 20,1969, Neil Armstrong walked on the surface of the moon. Untill then , no one knew 　 what the moon was like. Apollo see that the ground was hard and there (1)________ was a lot of dust that looked as gray powder(炸药). (2)________ Neil Armstrong travelled on from Earth in a spaceship (3)________ asked Apollo Ⅱ. Then, while Apollo Ⅱstayed in (4)________ space and orbited around the moon, Armstrong and (5)________ another astronaut , Edwin Aldrin, climbed a small (6)________ spaceship, called Eagle. This lunar module(登月舱) 　 took them to the moon . 　 　　The astronauts spent three hours pick up moon (7 ________ rocks. After that , they set on equipment to measure (8)________ the temperature and wind of the moon. When they (9)________ finished their work, they put an American flag (10)________ in the ground .