During endochondral ossification, the very first step in turninga hyaline model into bone is
| | secondary ossification |
| | bone collar formation |
| | primary ossification |
| | chondrocyte hypertrophy |
Action potentials on the surface of the sarcolemma originate atthe
| A. | T-tubules |
| B. | sarcomere |
| C. | neuromuscular junction |
| D. | Z-disk |
The most immediate, most effective source of ATP for a musclefiber that needs to perform at maximum output for a short period oftime (less than 10 seconds) is
| A. | aerobic respiration |
| B. | phosphagen system |
| C. | anaerobic respiration |
| D. | glycolysis |
During contraction of the sarcomere, the role of Ca+2is to
| A. | bind to troponin |
| B. | bind to tropomyosin |
| C. | provide the energy for myosin to pull on actin |
| D. | propagate action potentials |
