| 释义 |
phototropic, a. Biol.|ˌfəʊtəʊˈtrɒpɪk, -ˈtrəʊpɪk|
[f. photo- + Gr. -τρόπος turning + -ic: cf. Gr. τροπικός of or pertaining to turning.]
1. Exhibiting or characterized by phototropism. So photoˈtropically adv.
1899C. B. Davenport Exper. Morphol. ii. 438 Aquatic plants..are only very slightly phototropic. Ibid. 440 Etiolated willow shoots, upon which..the more strongly refractive rays only act phototropically. 1903Mark Anniversary Vol. xxiii. 455 Loeb maintained that butterflies as well as moths are positively phototropic. Ibid. 457 When feeding or near food the butterflies do not respond phototropically. 1943Vitamins & Hormones I. 211 In some structures also (Avena, Pilobolus, Phycomyces) carotenoid pigmentation has been shown to be concentrated in or restricted to the phototropically sensitive zones. 1972Plant Physiol. XLIX. 993/1 Etiolated plants are known to be more sensitive phototropically than are green ones. 1976Bell & Coombe tr. Strasburger's Textbk. Bot. (rev. ed.) 350 Phototropic behaviour is not confined to the higher plants; it occurs also in fungi and algae.
2. = photochromic a.
1900Jrnl. Chem. Soc. LXXVIII. ii. 125 Benzilosazone, salicylosazone, and vanillylosazone are, however, not phototropic. 1929Chem. Rev. VI. 220 Most phototropic substances exhibit phototropy only in the solid state. 1960New Scientist 2 June 1423/2 In the same family of substances some derivatives are phototropic while others, which resemble them closely, do not show the effect. 1971Materials & Technol. II. vi. 410 Phototropic glass is made by melting an alkali-alumino-borosilicate glass containing some lead and small amounts of silver, chloride, bromide, and iodide, forming the glass in the normal way, and then submitting the article to a heat treatment for several hours. |