Why do they need lochs in the panama canal?

Question

Why do they need lochs in the panama canal?

Answer 1

There are no locks in the suez canal..ships just sail from one end to the other..because the land is level,  but in panama the ships need to be lifted from sea level to the highest altitude of the land.  It is not practical to do this in one step.  Locks let the ships be raised or lowered as they are towed by locomotives from one side of Panama to the other.  Also (with out explaining here) the sea level is not the same on both sides of the the land.