Plant hormones serve as chemical messengers between cells and tissues. auxin is a plant hormone that causes the cells on the shady side of a plant shoot to elongate. the response enabled by auxin is known as:

for the answer to the question above, I believe the answer is "Phototropism".
in which the orientation of a plant or other organism in response to light, either toward the source of light or away from the source.

The answer is phototropism.
I hope this helps

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adioabiola adioabiola · Answer 2 · 2022-01-10T11:50:12+01:00

The response enabled by auxin is known as Phototropism

Auxin is a plant hormone and a key regulator of plant growth and development, orchestrating cell division, elongation and differentiation, embryonic development, root and stem tropisms, apical dominance, and transition to flowering.

Auxins also play a part in phototropism, an occurrence that involves plants bending or moving away from light. ...

The extra auxin present on the shaded side promotes more cell division and elongation, causing the plant to bend towards the sunlight after this lop-sided growth.