apogeotropism

[ ap-uh-jee-o-truh-piz-uhm ]

noun

, Biology.

1. growth or orientation away from the earth; negative geotropism.

apogeotropism

/ ˌæpəˌdʒɪəˈtrɒpɪk; ˌæpədʒɪˈɒtrəˌpɪzəm /

noun

1. negative geotropism, as shown by plant stems

Derived Forms

• apogeotropic, adjective

Other Words From

• ap·o·ge·o·trop·ic [ap-, uh, -jee-, uh, -, trop, -ik, troh, -pik], adjective
• apo·geo·tropi·cal·ly adverb

Word History and Origins

Origin of apogeotropism¹

First recorded in 1875–80; apo- + geotropism

Word History and Origins

Origin of apogeotropism¹

C19: from Greek apogaios away from the earth + tropos a turn

Example Sentences

Besides geotropism and apogeotropism, there is, according to Frank, an allied form of movement, * 'Manual of the Botany of the Northern United States,' 1856, p.

From Project Gutenberg

As soon as the faintest ray of light reaches a seedling, heliotropism will guide it through any crack in the soil, or through an entangled mass of overlying vegetation; for apogeotropism by itself can direct the seedling only blindly upwards.

From Project Gutenberg

But from observing the effects of placing plants in the dark, in which case several shoots became in two or three days upright or nearly upright, and when brought back into the light again became rectangularly curved, we believe that the bending is in part due to apheliotropism, apparently somewhat opposed by apogeotropism.

From Project Gutenberg

In two cases, namely with the cabbage and radish, the cotyledons of which rise almost vertically during the few first nights of their life, it was ascertained by placing young seedlings in the klinostat, that the upward movement was not due to apogeotropism.

From Project Gutenberg

Therefore, no more trials of this kind were made, which we now regret; as we afterwards found that when the tips of three cotyledons were cut off for a length of .2 inch, and of four others for lengths of .14, .12, .1, and .07 inch, and they were extended horizontally, the amputation did not interfere in the least with their bending vertically upwards, through the action of apogeotropism, like unmutilated specimens.

From Project Gutenberg