APP 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.四足動(dòng)物腰帶四周的杯狀的窩形結(jié)構(gòu),連接大腿骨(股......（本文共 261 字） [閱讀本文] >>
