Final answer:
Nyctinastic and thigmonastic movements are plant adjustments to environmental stimuli, with the prior responding to light and dark cycles and the latter to touch or mechanical stimuli.
Step-by-step explanation:
Nyctinastic and thigmonastic movements refer to the adjustments of plants in response to environmental stimuli. Nyctinastic movements are typically associated with the diurnal light and dark cycles, often seen in the opening and closing of flowers or leaves in response to the onset of darkness or light. An example of this would be the closing of a tulip's petals at night. On the other hand, thigmonastic movements are triggered by touch or mechanical disturbances. A well-known thigmonastic response is the rapid folding of the leaves of the Mimosa pudica plant, commonly known as the touch-me-not, upon being touched.