PLANTS
PLANT RESPONSES TO STIMULI
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
gravity
|
|
|
sunlight
|
|
|
water
|
|
|
wind
|
Detailed explanation-1: -The downward growth of roots due to the pull of gravity is positive geotropism .
Detailed explanation-2: -Roots grow downward, or towards the center of Earth, and away from light. These responses to external stimuli are called tropisms. Plants’ growth response to gravity is known as gravitropism; the growth response to light is phototropism. Both tropisms are controlled by plant growth hormones.
Detailed explanation-3: -Scientists have long speculated that plants bend in response to gravity due to the redistribution of the plant hormone auxin in the tip of the root.
Detailed explanation-4: -Geotropism is a type of tropism where plants show some growth in response to gravity. Roots growing downwards is an example of geotropism.