How do certain plants, like the sensitive plant (Mimosa pudica), fold their leaves in response to touch?

Question

How do certain plants, like the sensitive plant (Mimosa pudica), fold their leaves in response to touch?

In: Biology

Answer 1

Turgidity.  Which is the scientific term for swelling or stiffness caused by having liquid in an object. The leaves are usually out because they are turgid from water. But in response to a touch they quickly pump water out of the leaves and back into the stem. This causes the leaves to fold and be less likely to be damaged.

It is essentially the same thing as an erection response in a penis, but in the opposite direction.