如图为哺乳动物胚胎分割和性别鉴定示意图．请据图作答：

（1）胚胎分割时，一般采用发育良好、形态正常的____ ．对胚胎进行分割时，要特别注意将____ 均等分割，否则会影响分割后的胚胎恢复和进一步发育．来自同一胚胎分割产生的后代具有相同的遗传物质，因此，胚胎分割可以看作动物____ 的方法之一．

（2）通常胚胎干细胞可以从____ 中分离得到．

（3）早期胚胎中的胚胎干细胞，不仅可以被应用于哺乳动物胚胎性别鉴定，还可被应用____ 等领域．

教材中的下列实验设立了对照组的是（   ）

    Welcome to the town's greatest attraction --- Adam Square!

____

    Adam Square is right in the center of the town. It's on Adam Street. It's next to the WalMart Supermarket and across from the bank. There are lots of restaurants and coffee shops there.

____

    You can walk around the shops or you can have a cup of coffee. Try one of the popular coffee shops such as Domino. For a good meal, go to Pate's Pizzeria. It's really good and not too expensive.

____

    Why not visit Prince's Park? It's a good place for children. Take a number 32 bus to Market Square: you can buy fruit and vegetables there. If you like historic buildings, visit the Church of St. Nicholas.

____

    Come to Adam Square by bike. And it's OK to come here on foot. But you can't drive in Adam Square because there're no places for parking. Or if you're rich, you can take a taxi.

____

    It's a little far from the airport. It's about 40 minutes' walk. You can get here by bike in 20 minutes. But it will only take you 10 minutes to be here in a taxi

下列能直接看到的是（ )。