下列生物新个体的产生，属于无性生殖的是（　　）

①椒草的叶片长出新植株 ②蛙的受精卵发育成蝌蚪 ③草履虫通过分裂产生新个体 ④玉米种子种下长出玉米植株 ⑤马铃薯的块茎发芽生根 ⑥蚕蛾的受精卵发育成蚕 ⑦代孕母羊产下克隆羊多莉．

战国时期除道、儒、墨、法四大学派之外，还有一些有影响的学派。其中主要有讨论合纵、连横的纵横家，提倡重农政策和探究农业技术的农家，研究军事理论的兵家,以及综合各派学说的杂家等。这表明当时(   )

采用下图所示的方法获得纯合高蔓抗病番茄植株（两对相对性状独立遗传）。下列叙述错误的是（）

How do we know the weather? We learn it on the radio and TV every day. Different countries have different weather. For example, the weather in Australia is different from that in China. Because the seasons in Australia are the opposite. Its summer is from December to February. But in our country, it's winter this time. And its winter is in June, July and August. So when it's spring in China, it's autumn in Australia. Isn't it interesting?