Virtually all species in nature, from single-cell organisms to mammals, including humans, exhibit a daily cycle of activity called circadian rhythm.
几乎自然界中所有的物种，从单细胞生物到哺乳动物(包括人类)，都具有一种日常活动周期，称为昼夜节律。
2
Calcium is important in the physiologic process of muscle or nervous reaction, nervous impulse transmission, heartbeat rhythm maintenance, blood solidification, cell coherence and so on.
在神经，肌肉应激，神经冲动的传递，心动节律的维持，血液凝固，细胞粘着等生理过程中，具有重要的意义。
3
It is well known that the developmental inherent rhythm occurs during the development of secondary vascular tissue. Synchronously, the cell ergastic substance shows dynamic changes.