Simplify the following text for a Grade 7 native English-speaking person.
Original: They have a `` crown '' of solid tentacles whose cilia generate water currents that draw food particles towards the mouth , and both the mouth and anus lie inside the `` crown '' .
Simplified: They are filter-feeders , with a crown of tentacles whose cilia generate water currents towards the mouth . Both the mouth and anus lie inside the crown .