1. **Problem:** Describe how a buoy anchored to the ocean floor moves as a wave passes by. 2. **Understanding wave motion:** Ocean waves are typically surface waves that cause water particles to move in circular orbits. 3. **Key concept:** For a buoy anchored to the ocean floor, it cannot move horizontally with the wave because it is fixed in place. 4. **Wave effect on buoy:** The buoy will move mostly up and down as the wave passes, following the vertical motion of the water surface. 5. **Explanation:** The buoy rides the wave crest by rising and then falls into the trough, moving vertically but not traveling horizontally with the wave. 6. **Summary:** The buoy oscillates vertically in place as the wave energy passes through the water. **Final answer:** The buoy moves up and down vertically as the wave goes by, but it does not move horizontally because it is anchored to the ocean floor.