The ends of the long bones also remain cartilaginous .
长骨的末端仍然是软骨组织。
Branches and cladodes generally not cartilaginous denticulate .
一般的分枝和叶状枝并非具软骨质小齿。
Twenty-three years later marine biologists studying elasmobranch ( the subclass of cartilaginous fishes that include sharks skates and rays ) animals employ satellite tracking genetic analysis and high-definition cameras to broaden their knowledge of shark biology and behavior .
