如图曲线表示人体血液内某种激素的含量在一昼夜内变化情况,该激素是( )
A:性激素
B:甲状腺激素
C:生长激素
D:胰岛素
防止食品腐败可以采用不同的方法,对香菇这种食品的保存方法常采用( )
One day Eddie and Hobo looked at the ____. Eddie thought he saw a____but Hobo thought it was a ____. Because Hobo saw one ____. Eddie thought there were many bright ____and it was too____, so it couldn't be a plane.
某学校的生物课外小组开展大白菜丰产实验,每棵重约4Kg。请问大白菜增产的物质主要来自 ( )
人和动物细胞都没有细胞壁,细胞质中也没有叶绿体.( )