关于肌肉的收缩形式不正确的是（）
A.等长收缩只有张力的增加而无长度的缩短
B.等长收缩时，肌肉作用的物体未发生位移，所以未对物体做功
C.等张收缩只有长度的变化而无张力的改变
D.等张收缩时，肌肉收缩时有关节的运动，所以它对物体做了功
E.人体骨骼肌的收缩的形式不可能为混合式收缩
参考答案：E
解析：人体骨骼肌的收缩的形式均为混合式收缩，所以E答案错误。
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a timetable and organize (组织) what you are going to do. Then you will not (3)_____ bored (无聊的) during the long summer holiday! Here are what some (4)_____ do during their long holidays: ◆ (5)_____ pictures or make something. ◆ Listen to music. ◆ Visit friends. ◆ _____. ◆ Play sports in the park with friends. ◆ Write some short (7)_____. ◆ Help parents do the housework. ◆ (8)_____ how to cook. ◆ Go to the movies, watch TV or play on the computer. I (9)_____ these ideas are helpful (有帮助的) to you. Stay happy during your long holiday and (10)_____ your holiday activities. |