Skip to main content
Select Source:

geotropism

geotropism (gravitropism) The growth of plant organs in response to gravity. A main root is positively geotropic and a main stem negatively geotropic, growing downwards and upwards respectively, irrespective of the positions in which they are placed. For example, if a stem is placed in a horizontal position it will still grow upwards. It is thought that mobile membrane-bound clusters of starch grains (amyloplasts) sink to the bottom of a plant cell, under the influence of gravity, and somehow create a physiological asymmetry within the cell. This results in differential growth of the upper and lower sides of the cell, and hence upward or downward curvature of the organ concerned, depending on whether it is a root or a shoot. The biochemical mechanisms of this differential growth remain largely unknown, although auxins are required for geotropism in shoots, and also possibly in roots, and there is evidence that calcium ions play a role too. See tropism.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"geotropism." A Dictionary of Biology. . Encyclopedia.com. 22 Apr. 2018 <http://www.encyclopedia.com>.

"geotropism." A Dictionary of Biology. . Encyclopedia.com. (April 22, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/geotropism-1

"geotropism." A Dictionary of Biology. . Retrieved April 22, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/geotropism-1

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

geotropism

ge·ot·ro·pism / jēˈätrəˌpizəm/ • n. Bot. the growth of the parts of plants with respect 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. DERIVATIVES: ge·o·trop·ic / ˌjēəˈträpik; -ˈtrō-/ adj.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"geotropism." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. 22 Apr. 2018 <http://www.encyclopedia.com>.

"geotropism." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (April 22, 2018). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/geotropism

"geotropism." The Oxford Pocket Dictionary of Current English. . Retrieved April 22, 2018 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/geotropism

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

geotropism

geotropism A directional movement of a plant in response to the stimulus of gravity. Primary tap roots show positive geotropism; vertical primary shoots show negative geotropism; horizontal stems and leaves are diageotropic (see diageotropism); and branches and secondary roots at oblique angles are plagiogeotropic.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"geotropism." A Dictionary of Ecology. . Encyclopedia.com. 22 Apr. 2018 <http://www.encyclopedia.com>.

"geotropism." A Dictionary of Ecology. . Encyclopedia.com. (April 22, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/geotropism

"geotropism." A Dictionary of Ecology. . Retrieved April 22, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/geotropism

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

geotropism

geotropism A directional movement of a plant in response to the stimulus of gravity. Primary tap roots show positive geotropism; vertical primary shoots show negative geotropism; horizontal stems and leaves are diageotropic (see DIAGEOTROPISM); and branches and secondary roots at oblique angles are plagiogeotropic.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"geotropism." A Dictionary of Plant Sciences. . Encyclopedia.com. 22 Apr. 2018 <http://www.encyclopedia.com>.

"geotropism." A Dictionary of Plant Sciences. . Encyclopedia.com. (April 22, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/geotropism-0

"geotropism." A Dictionary of Plant Sciences. . Retrieved April 22, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/geotropism-0

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.