Final answer:
The worms' behavior indicated taxis, which is a directed movement toward or away from a stimulus; this is evidenced by consistent movement patterns in relation to the stimulus, resembling the positive chemotaxis displayed by the protozoan Tetrahymena thermophila.
Step-by-step explanation:
The conclusion that the worms' behavior demonstrated taxis is supported by observations indicating a directed movement in response to a stimulus. Taxis is when an organism moves toward (positive) or away (negative) from a stimulus which can be in multiple forms such as light (phototaxis), chemical signals (chemotaxis), or gravity (geotaxis).
If a worm is observed moving consistently towards a certain stimulus, it suggests that the worm is exhibiting a form of positive taxis. In other words, the organism adjusts its direction of movement based on the location or intensity of the stimulating source which, in this case, could be a chemical substance that is attracting or repelling it.
For example, positive chemotaxis is seen in the protozoan Tetrahymena thermophila, which changes its swimming patterns, such as frequency of turning, to move toward the higher concentration of a chemical attractant. Similarly, if the worms' movements indicate they are consistently moving toward or away from a specific stimulus, it would affirm that they are displaying taxis.