Why Plants Grow Upwards Defying Force Of Gravity – News18

In a thought-provoking exploration of plant growth dynamics, a curious Quora user delved into the intriguing question of how they defy gravity to grow upwards while their roots extend in the opposite direction. A passionate biologist took up the challenge and shed light on this phenomenon, attributing it to the fascinating concept of gravitropism.

According to the biologist, the key player in this botanical balancing act is the presence of auxin hormones within the plant. These hormones stimulate rapid cell division, dictating the direction of growth. When a plant shoots points straight up, gravity ensures that the concentration of auxins remains higher at the base, prompting the plant to grow vertically. However, if the plant is tilted sideways, the increased gravitational pull on the lower side results in a higher concentration of auxins, promoting enhanced cell growth. This, in turn, causes the shoot to bend and grow upwards, effectively countering the initial tilt.

Taking the discussion to a more scholarly level, an Associate Professor in Botany contributed another layer of scientific explanation. He highlighted two types of plant movements: growth-dependent movements, also known as tropic movements, and non-growth-dependent movements, termed nastic movements. Tropic movements encompass five types, including phototropism (towards light), geotropism (towards soil), hydrotropism (towards water), chemotropism (in response to chemical stimuli), and thigmotropism (climbing with support). These movements are driven by the plant’s growth and response to various stimuli.

The user also touched upon the intriguing idea that plants, seemingly defying gravity, grow towards sunlight, which is conventionally considered “up.” This perspective challenges the notion that gravity is an omnipotent force, emphasising that it is not an insurmountable barrier – humans can walk on the ground. This helps plants to grow in seeming defiance of gravity.