Sensitive plants (Mimosa Pudica) close their leaves when touched or shaken. This is thought to be a defensive measure to prevent from getting eaten. The movement startles animals and they go looking for a less active plant to eat. The leaves, which grow in a parallel row along the stem, open again within an hour. It is very popular due to it's particular trait and not only makes a great gift but is also a great house plant.
Approximate Size: 4"