The cells and tissues that make up our body manage contradictory mechanical demands. It is crucial for their survival to be able to withstand large mechanical loads, but it is equally crucial for them to produce forces and actively change shape during biological processes such as tissue growth and repair. The mechanics of cells and tissues is determined by scaffolds of protein polymers known as the cytoskeleton and the extracellular matrix, respectively. Experiments on model systems reconstituted from purified components combined with polymer physics concepts have already uncovered some of the mechanisms that underlie the paradoxical mechanics of living matter. Initial work focused on explaining universal features, such as the nonlinear elasticity of cells and tissues, in terms of polymer network models. However, there is a growing recognition that living matter exhibits many advanced mechanical functionalities that are not captured by these coarse-grained theories. Here, we review recent experimental and theoretical insights that reveal how the porous structure, structural hierarchy, transient crosslinking and mechanochemical activity of biopolymers confer resilience combined with the ability to adapt and self-heal. These physical concepts increase our understanding of cell and tissue biology and provide inspiration for advanced synthetic materials.

构成我们身体的细胞和组织管理着相互矛盾的机械需求。能够承受较大的机械载荷对于它们的生存至关重要，但是对于它们在组织生长和修复等生物过程中产生力并主动改变形状同样至关重要。细胞和组织的力学由分别称为细胞骨架和细胞外基质的蛋白质聚合物支架决定。由纯化成分重构的模型系统的实验结合高分子物理概念，已经发现了构成生物悖论力学基础的一些机理。最初的工作着眼于根据聚合物网络模型解释通用特征，例如细胞和组织的非线性弹性。然而，人们越来越认识到，生物具有许多先进的机械功能，而这些功能并未被这些粗粒度的理论所捕获。在这里，我们回顾了最近的实验和理论见解，这些见解揭示了生物聚合物的多孔结构，结构层次，瞬态交联和机械化学活性如何赋予弹性以及适应能力和自我修复能力。这些物理概念加深了我们对细胞和组织生物学的理解，并为先进的合成材料提供了灵感。生物聚合物的瞬时交联和机械化学活性赋予其弹性以及适应和自我修复的能力。这些物理概念加深了我们对细胞和组织生物学的理解，并为先进的合成材料提供了灵感。生物聚合物的瞬时交联和机械化学活性赋予其弹性以及适应和自我修复的能力。这些物理概念增加了我们对细胞和组织生物学的理解，并为先进的合成材料提供了灵感。