《英文msh詞典》Cycle,Activity
[入口詞] Cycle,Activity
[主題詞] Activity Cycles
[英文釋義] Bouts of physical irritability or movement alternating with periods of quiescence. It includes biochemical activity and hormonal activity which may be cellular. These cycles are shorter than 24 hours and include sleep-wakefulness cycles and the periodic activation of the digestive system.