Ques. 1AIPMT 2005
The ability of the Venus Flytrap to capture insects is due to
- specialized “muscle-like” cells
- chemical stimulation by the prey
- a passive process requiring no special ability on the part of the plant
- rapid turgor pressure changes.
Answer
(4) rapid turgor pressure changes.
Solution
As per NCERT, in insectivorous plants like the Venus flytrap the leaves are modified to trap insects.
When an insect touches the trigger hairs on the leaf lobes, ions move and water rapidly leaves the cells of the midrib (hinge) region.
⇒ The sudden loss of turgor in these cells snaps the two lobes shut over the insect (a seismonastic movement).
∵ Plants have no muscle cells, and the movement is an active, stimulus-triggered response.
∴ Capture of insects is due to rapid turgor pressure changes.
Answer: (4)