Derek Harding
21485917
EDF4402 Assignment 1A – CoRe of a Big Idea
Group: Derek Harding, Leigh Jose, Alex Jackson, Simon Steele, Tyson Mitchell.
Unit/Area of Study: Unit 2, Area of Study 1: Adaptations of organisms.
The Big Idea: Plants have a directional growth response to environmental stimuli (Tropisms).
What you intend the students to learn about this idea:
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Plants have a directional growth response to environmental stimuli know as tropisms.
Such stimuli are sunlight (Phototropism), water (Hydrotropism), gravity (Geotropism)
and touch (Thigmotropism).
The physiology behind the directional growth responses.
Positive and negative tropisms.
Why is it important for students to know this:
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To solidify the knowledge that plants are living organism’s part of our environment and
ecosystems. Therefore, gaining a respect that plants play a role in our living lives.
That like humans, plants respond to basic functional needs such as water and food
(Sunlight). They adapt to their environment.
Botanic implications such a providing water and light for plants to survive.
What else you know about this idea (That you do not intend students to know yet):
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Non-directional growth responses (Nastic movements) to stimuli such as temperature or
humidity.
Physiological effects of non-tropic stimuli on the plants growth response (E.g. Virus).
Not to be confused with ‘What would happened if we covered the tip of the plant during
phototropism.
Difficulties/limitations connected with teaching this idea:
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The physiology behind tropisms is invisible to the eye and cannot be physically
demonstrated. Video’s try to depict functioning but are only simple representations.
Connecting the big idea of tropisms to the big picture of adaptations, environmental
factors and distribution of living things.
Derek Harding
21485917
Knowledge about students’ thinking which influences your teaching of this idea:
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Students try to over-simplify: The idea of tropisms is not as simple as plant contacts light
and consequently bends toward it.
Students don’t always understand ‘too much of a good thing can be bad’ concept: The
idea that a plant will not always have a growth response toward a stimulus (I.e. Negative
tropisms - too much sun and the plant well move toward the shade).
Students relate positive to ‘up’ or ‘toward’: Distinguishing between up and down in
relation to positive and negative tropisms could be problematic (I.e. Root movement
downward is a positive tropism, not negative).
Other factors that influence your teaching of this idea:
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There are some really good ideas for practical activities for this big idea that I would
likely want to try.
There is a moral aspect that can be drawn upon in relation to planting trees and helping
the environment stay clean.
Teaching procedures (And particular reasons for using these to engage with this idea):
Question building: Directing a whole classroom discussion to tease out prior knowledge and
have students thinking about not only the big idea, but how it relates to the overall area of study
topic. Why do plants need to adapt? What environmental factors cause certain plants to respond
in specific ways? Does this affect their distribution? What are the specific responses plants have
and why might this be? Etc.
Video representation: Can be used to show plants directional growth responses to stimuli
(Tropisms) to prove it does happen, but also to demonstrate the physiology behind these.
Simplistic videos will help with the explanation that auxin hormones run down the dark side of
plant cause it to bend toward the stimulus (Sunlight). Can also help remove the misconception
between positive tropisms moving ‘up’ or ‘forward’ and how it differs from negative tropisms.
Practical: There are some very engaging practicals that will help link content knowledge with
hands on learning. Design or use existing practicals and develop questions tailored to your
students. These would include simple define questions and range up to apply your knowledge to
certain scenarios. A written report upon conclusion would be expected.
Derek Harding
21485917
Specific ways of ascertaining students’ understanding or confusion around this idea
(Include likely range of responses):
Two of the teaching procedures listed above are not only designed to gain maximum
understanding but to aide with ascertaining student understanding.
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Question building: Allows for teacher identification of current/base knowledge and any
misconceptions that need to be removed.
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Practical: Responses to the questions within the written report will be a strong identifier
of student level of knowledge. Whilst simple define questions will show rote learning
ability, the application of knowledge questions, such as ‘what would happen in the
scenario’ type question will give a strong indication of true understanding of not only
directional growth responses, but the physiology behind this (E.g. What would happen if
the tip of a stem where auxins are housed is cut off? Etc.).