Control and Coordination in plants

Have you seen the Touch-Me-Not plant ( Mimosa pudica ) ?

How does it behave when touched ?

Th e leaves curl away and droop.

This is how the Touch-Me-Not plant responds to touch .

Think about a seed germinating , 

• Roots grow in the downward direction  
• Shoot containing stem, leaves, flowers etc. grow in the upward direction .

This is another kind of response displayed by plants.

Observe the two kinds of responses;

We know plants do not have nervous systems or muscles for movement. So what causes these responses to stimuli in plants?