Tropismeja

Tropismeja is a term used in biology to describe the directional growth of a plant in response to a stimulus. This movement is a response to an external factor, such as light, gravity, touch, or chemicals. Tropisms are crucial for plant survival and adaptation, allowing them to optimize their growth towards resources like sunlight or water, or away from harmful conditions.

Phototropism is the growth response to light. Plants typically exhibit positive phototropism, bending their shoots towards a light source to maximize photosynthesis. Gravitropism, also known as geotropism, is the response to gravity. Shoots usually show negative gravitropism, growing upwards against gravity, while roots display positive gravitropism, growing downwards into the soil. Thigmotropism is the directional growth in response to touch, commonly seen in climbing plants like vines that coil around supports. Hydrotropism is the growth towards or away from water, which is vital for root development. Chemotropism involves growth in response to chemical stimuli, influencing processes like pollen tube growth towards the ovule. These tropisms are mediated by plant hormones, primarily auxins, which accumulate on one side of the plant organ and stimulate cell elongation, leading to the bending or directional growth.