What is meant by the term tropism?
Reveal answer
Directional growth response to a directional stimulus.
Key words: tropism
3(j) CO-ORDINATION AND RESPONSE · RECALL
3.33 Plant responses to stimuli
15 recall questions. Answer from memory, reveal the answer, then rate yourself. Ratings stay on this device.
Ratings are saved in this browser on this device, under a KS4 key kept separate from International A Level recall. Written answers are temporary and cleared when you leave the page. Use Reset to clear the ratings on this device.
What is meant by the term positive tropism?
Reveal answer
Growth toward a stimulus.
Key words: positive tropism
What is meant by the term negative tropism?
Reveal answer
Growth away from a stimulus.
Key words: negative tropism
What is meant by the term turgor response?
Reveal answer
Movement caused by changes in water pressure inside cells rather than growth.
Key words: turgor response
Examples of plant responses: for Directional light, give the response example and the possible value.
Reveal answer
Response example: Shoot phototropism. Possible value: Improves light capture.
Key words: Directional light
Examples of plant responses: for Gravity, give the response example and the possible value.
Reveal answer
Response example: Root positive geotropism. Possible value: Anchorage and soil access.
Key words: Gravity
Examples of plant responses: for Water gradient, give the response example and the possible value.
Reveal answer
Response example: Root hydrotropism. Possible value: Improves water uptake.
Key words: Water gradient
Examples of plant responses: for Touch, give the response example and the possible value.
Reveal answer
Response example: Tendril coiling/thigmotropism. Possible value: Supports climbing.
Key words: Touch
Examples of plant responses: for Water stress, give the response example and the possible value.
Reveal answer
Response example: Stomatal closure. Possible value: Reduces water loss; not a growth tropism.
Key words: Water stress
True or false, and why? “Plants cannot respond because they lack nerves.”
Reveal answer
False. They use chemical, electrical, growth and turgor responses.
True or false, and why? “All plant movement is a tropism.”
Reveal answer
False. A tropism is specifically directional growth.
True or false, and why? “Positive means beneficial and negative means harmful.”
Reveal answer
False. They describe direction toward or away from the stimulus.
What is phototropism?
Reveal answer
A growth response of a plant to the direction of light.
Key words: light
What is geotropism?
Reveal answer
A growth response of a plant to gravity.
Key words: gravity
Why is positive geotropism useful to a root?
Reveal answer
Grows down into the soil → anchorage and uptake of water and mineral ions.
Key words: anchorage