| Answer | Crossword Clue |
|---|---|
| ESS | What opens and closes safes? |
| door | an entrance that opens and closes |
| doors | DOOR, an entrance that opens and closes |
| shutters | A device that opens and closes to expose the film in a camera |
| gating | the process by which a channel in a cell membrane opens or closes |
| latches | The part of a knitting machine needle that closes or opens to hold or release the wool |
