Hydrotropism

Hydrotropism (hydro- 'water'; tropism 'involuntary orientation by an organism, that involves turning or curving as a positive or negative response to a stimulus') is a plant's growth response in which the direction of growth is determined by a stimulus or gradient in water concentration. A common example is a plant root growing in humid air bending toward a higher relative humidity level. Hydrotropism (hydro- 'water'; tropism 'involuntary orientation by an organism, that involves turning or curving as a positive or negative response to a stimulus') is a plant's growth response in which the direction of growth is determined by a stimulus or gradient in water concentration. A common example is a plant root growing in humid air bending toward a higher relative humidity level.