A cup-shaped socket on eachside of the pelvic girdle in tetrapods thatholds the rounded head of the thigh bone (fe-mur) to form the hip joint. This ball-and-socket arrangement allows for great stabilityand a wide range of movement.四足动物腰带四周的杯状的窝形结构,连接大腿骨(股......(本文共 261 字) [阅读本文] >>