The Detector of Light During De-Etiolation (Greening)of a Tomato Plant

Question

The detector of light during de-etiolation (greening)of a tomato plant is (are)
A) carotenoids.
B) xanthophylls.
C) phytochrome.
D) chlorophyll.
E) auxin.

Accepted Answer

Phytochrome is the photoreceptor responsible for detecting and responding to light during de-etiolation (greening) of plants. It exists in two forms, Pr (inactive) and Pfr (active), and the conversion between the two forms triggers a variety of responses in plants, including greening and the opening of stomata. Carotenoids, xanthophylls, chlorophyll, and auxin are not directly involved in detecting light during de-etiolation.