00:01
So gravitropism refers to the growth or movement of a plant in response to gravity.
00:05
It can either be positive or negative, depending on the part of the plant.
00:09
The root system generally exhibits positive gravitropism, growing downward into the soil, while the shoot system shows negative gravitropism growing upwards towards the light.
00:21
This tropism allows the plants to establish and maintain their orientation with respect to gravity, helping them optimize nutrient uptake from the soil to maximize exposure to sunlight.
00:32
Phototropism is the growth or movement of a plant in response to light.
00:37
It is characterized by the curvature or bending of a plant of plant organs toward a light source.
00:42
The most common example of bending of stems towards sunlight.
00:48
This phenomenon occurs due to the differential distribution of the plant hormone auxin, which accumulates on the shaded side, causing cells to elongate and resulting in the bending towards the light.
01:00
Phototropism enables plants to maximize their exposure to light, which is crucial for photosynthesis, the process by which they convert light energy into chemical energy for growth and survival.
01:15
Thigmotropism refers to a growth or movement of a plant in response to touch or mechanical stimuli...