A Mitzvah In The Mouth
When you come home on Seder night, you are presumably very hungry. You’ve spent the whole day preparing for the Seder and for Pesach. Chametz is forbidden most of the day. Matzah is forbidden all day.
Pesach
Romaine Lettuce for Karpas in the Gemara
Using romaine lettuce for karpas at the Seder when it is also used for marror, and when the berachah on marror is said.