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geotropism

Line breaks: geo|trop¦ism
Pronunciation: /ˌdʒiːə(ʊ)ˈtrəʊpɪz(ə)m
 
/

Definition of geotropism in English:

noun

[mass noun] Botany
The growth of the parts of plants in response to the force of gravity. The upward growth of plant shoots is an instance of negative geotropism; the downward growth of roots is positive geotropism.
Example sentences
  • It was shown that gaseous ethylene inhibits both growth and geotropism in plants, and ethylene is endogenously produced by fruits.
  • Geotropism occurs in two forms: positive geotropism to which the root responds by growing downward; and a negative geotropism, which causes the stem to grow upward.
  • Transversal geotropism is a direction of growth that is vertical to the shoot axis.

Origin

late 19th century: from geo- 'earth' + Greek tropē 'turning' + -ism.

Derivatives

geotropic

1
Pronunciation: /dʒiːə(ʊ)ˈtrəʊpɪk, -ˈtrɒpɪk/
adjective
Example sentences
  • Seed viability was assessed using the criterion of normal seedling development, i.e. emergence of the hypocotyl, radicle geotropic growth, and the opening of cotyledonary leaves.
  • Cholodny proposed that ‘growth hormones play an essential role in the mechanism of the geotropic reaction’.
  • These stem adaptations, combined with the presence of adventitious roots and negatively geotropic roots in nitrogen-fixing alders, facilitate the supply of oxygen in waterlogged soils.

Definition of geotropism in:

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