She's so majestic. -- The soft body of a clam is protected by a hard shell. The shell is made of a mineral called calcium carbonate. Two muscles—one on each end of the shell—keep the shell closed. To move, a clam uses a muscular “foot” that pushes out of the shell. A clam takes in and passes out water through two siphons, or tubes. The siphons may look like a long “neck” sticking out of the shell. - #Britannica | Bad Science Jokes