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what are plant hormones ? explain geotropisum and hydrotropisum ?
The growth and development of many plants are regulated by the activity of plant hormones. Hormones are biochemical substances produced in one part of a plant and transported to a different part where they exert a particular effect.  Auxins abscisic acid, gibberellins and the cytokinins are some of them.


Geotropism is the term applied to the consequent orientation response of growing plant parts. Roots are positively geotropic, They  bend and grow downwards, towards the center of the Earth.  In contrast, shoots are negatively geotropic. They  bend and grow upwards, or away, from the surface.

 Hydrotropism is a plant's growth response to water concentrations. The response can be positive (towards the water) or negative (away from the water). Roots, for instance, are positively hydrotropic.


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