问题
填空题
由受精卵发育成新个体的生殖方式叫______；不经过两性生殖细胞结合，由母体发育成新个体的生殖方式叫______．
答案
有性生殖是指：由两性生殖细胞结合形成受精卵，由受精卵发育成新个体．
无性生殖是指：不经过两性生殖细胞结合，由母体直接发育成新个体．
二者的根本区别在于是否有受精卵的形成．
故答案为：有性生殖；无性生殖
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由受精卵发育成新个体的生殖方式叫______；不经过两性生殖细胞结合，由母体发育成新个体的生殖方式叫______．
有性生殖是指：由两性生殖细胞结合形成受精卵，由受精卵发育成新个体．
无性生殖是指：不经过两性生殖细胞结合，由母体直接发育成新个体．
二者的根本区别在于是否有受精卵的形成．
故答案为：有性生殖；无性生殖
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| Tina and Tara are twin sisters. They look 1 , but they also have some differences. Mr. Black is their old grandfather. One day, he came to see his two granddaughters 2 two gifts. When he came into the house he saw Tina and 3 her one gift. After a while, when he got into the garden he saw 4 granddaughter-"Tara". In fact, that was Tina. When he gave the other gift to her, she said, "you have given me one." "No, I gave a gift to your 5 -Tina." "Oh, my grandpa, I am Tina." Just then, Tara came into the garden, too. "Now, grandpa, can you tell me the differences 6 us?" "'No, I can't. Can you 7 me?" "Yes, look, Tara is a little taller 8 me. Her hair is longer and curlier, then 9 . Now grandpa, can you see?" "Yes, now I can tell you 10 Tara. Tara, here is the gift for you." "Thank you for your gift, grandpa." With the words, they all laughed happily. | ||||
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