Chapter 1 (1.3) Flashcards
What are the types of responses of plants?
-Tropism
-Nastic movement
What is tropism?
Tropism is the directional response of plants towards stimuli coming from a certain direction
What do most plants respond to?
-Light
-Gravity
-Water
-Touch
What is tropic movement?
Tropic movement is the movement of growth of a plant in a specific direction in response to a stimulus
What is the difference between positive tropism and negative tropism?
Positive tropism is when a part of the plant grows towards the stimulus, but negative tropism is when a part of a plant grows away from the stimulus
What is phototropism?
Phototropism is the movement or growth of plants in response to light
What does the respond of plants depends on?
The respond of plants depends on the direction of the source of light
When shoot grow towards the light, what is this phenomenon called?
Positive phototrophic
When root grow away from the light, what is this phenomenon called?
Negatively phototropic
What is the importance of the response when shoots of plants grow towards light?
To ensure leaves obtain the sunlight for photosynthesis
What is geotropism?
Geotropism is the movement or growth of the tips of the shoots and roots of plants in response to gravity
When root grow downwards in the direction of gravity, what is this phenomenon called?
Positive geotropism
When shoots grow in the opposite direction of gravity, what is this phenomenon called?
Negative geotropism
What is the importance of the response when roots of plants grow towards gravity ?
-Important for roots to grow deep in the soil
-Give support to plants
What is hydrotropism?
Hydrotropism is the movement or response of plants in response to water or moisture
When roots grow towards water, what is this phenomenon called?
Positive hydrotropism
When shoot grow away from water, what is this phenomenon called?
Negative hydrotropism
What is the importance of the response when roots of plants grow towards water?
Helps plants absorb dissolved minerals and water for photosynthesis
What is thigmotropism?
Thigmotropism is a tropic response in which the stimulus is touch or contact.
When roots grow away from solid object such as stone, what is this phenomenon called?
Negative thigmotropism
When tendrils and stems tend to grow towards the object that they come into contact with, what is this phenomenon called?
Positive thigmotropism
What is the importance of thigmotropism?
-Helps soft-steamed plants to get support from the object they wrap around
-To grow upward to obtain sunlight
What is nastic movement?
Nastic movement is the response of plants towards stimuli such as touch and does not depend on the direction of stimuli
What is the example of nastic movement?
The opening and closing movement of the Mimosa pudica leaflets
What are the characteristics of nastic movement?
-Does not depend on the direction of the stimulus
-Movement is reversible
