Carnivorous plants are plants that derive some or most of their nutrients (but not energy) from trapping and
consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants have adapted to grow in
places with high light where the soil is thin or poor in nutrients, especially nitrogen, such as acidic bogs and rock outcroppings .
Pitfall traps (pitcher plants)
trap prey in a rolled leaf that contains a pool of digestive enzymes or
bacteria
The traps are very similar, with
leaves whose terminal section is divided into two lobes, hinged along the
midrib. Trigger hairs (three on each lobe in Dionaea muscipula, many more in
the case of Aldrovanda) inside the trap lobes are sensitive to touch. When a
trigger hair is bent, stretch-gated ion channels in the membranes of cells at
the base of the trigger hair open, generating an action potential that
propagates to cells in the midrib.[17] These cells respond by pumping out ions,
which may either cause water to follow by osmosis (collapsing the cells in the
midrib) or cause rapid acid growth.[18] The mechanism is still debated, but in
any case, changes in the shape of cells in the midrib allow the lobes, held
under tension, to snap shut,[17] flipping rapidly from convex to concave[19]
and interring the prey. This whole process takes less than a second. In the
Venus flytrap, closure in response to raindrops and blown-in debris is
prevented by the leaves having a simple memory: for the lobes to shut, two
stimuli are required, 0.5 to 30 seconds apart
