Read the given passage and answer the questions that follow.
Do plants feel pain? Given that plants do not have pain receptors, nerves, or a brain, they do
not feel pain as we members of the animal kingdom understand it. Uprooting a carrot or
trimming a hedge is not a form of botanical torture, and you can bite into that apple without
worry. However, it seems that many plants can perceive and communicate physical stimuli
and damage in ways that are more sophisticated than previously thought.
Some plants have obvious sensory abilities, such as the Venus flytrap and its incredible traps
that can close in about half a second. Similarly, the sensitive plant rapidly collapses its leaves
in response to touch, an adaptation that might serve to startle away potential herbivores.
While these plants visibly display a clear sensory capacity, recent research has shown that
other plants are able to perceive and respond to mechanical stimuli at a cellular level.
Arabidopsis (a mustard plant commonly used in scientific studies) sends out electrical
signals from leaf to leaf when it is being eaten by caterpillars or aphids, signals to ramp up its
chemical defenses against herbivory. While this remarkable response is initiated by physical
damage, the electrical warning signal is not equivalent to a pain signal, and we should not
anthropomorphize an injured plant as a plant in pain. Plants have exceptional abilities to
respond to sunlight, gravity, wind, and even tiny insect bites, but (thankfully) their evolutionary
successes and failures have not been shaped by suffering, just simple life and death.
Which of the following types of responses of the Venus flytrap does the passage refer to?