Cells are ion conductive gels surrounded by a ~5-nm-thick insulating membrane, and molecular ionic pumps in the membrane establish an internal potential of approximately -90 mV. This electrical energy store is used for high-speed communication in nerve and muscle and other cells. Nature also has used this electric field for high-speed motor activity, most notably in the ear, where transduction and detection can function as high as 120 kHz. In the ear, there are two sets of sensory cells: the "inner hair cells" that generate an electrical output to the nervous system and the more numerous "outer hair cells" that use electromotility to counteract viscosity and thus sharpen resonance to improve frequency resolution. Nature, in a remarkable exhibition of nanomechanics, has made out of soft, aqueous materials a microphone and high-speed decoder capable of functioning at 120 kHz, limited only by thermal noise. Both physics and biology are only now becoming aware of the material properties of biomembranes and their ability to perform work and sense the environment. We anticipate new examples of this biopiezoelectricity will be forthcoming.

中文翻译：

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生物学中的膜机电学，重点是听力。


细胞是由约 5 nm 厚的绝缘膜包围的离子传导凝胶，膜中的分子离子泵建立约 -90 mV 的内部电位。这种电能存储用于神经、肌肉和其他细胞的高速通信。大自然也将这种电场用于高速运动活动，尤其是在耳朵中，其中的传导和检测可以高达 120 kHz。在耳朵中，有两组感觉细胞：向神经系统产生电输出的“内毛细胞”和更多的“外毛细胞”，它们利用电动势来抵消粘度，从而锐化共振以提高频率分辨率。大自然在一场非凡的纳米力学展览中，用柔软的水性材料制成了麦克风和高速解码器，能够以 120 kHz 的频率运行，仅受热噪声的限制。物理学和生物学现在才开始意识到生物膜的材料特性及其执行工作和感知环境的能力。我们预计这种生物压电的新例子将会出现。