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This activity was designed to allow students
to appreciate how ideas from different
science disciplines can be synthesised,
specifically in the context of a model
of plant nutrition.
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| Overview of the activity |
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In this activity, teams
of (ideally) four students work as project teams,
and are assigned roles as project manager, biologist,
chemist and physicist. The team has to produce a
poster to explain how a plant manages to obtain
the energy and materials needed to live.
During the ASCEND project this activity, and the
following one, were undertaken by groups of students
during the same 90 minute sessions. They may easily
be separated and used independently. (You should
omit the instruction about project brief 2 from
the project manager’s brief sheet if the group are
not to proceed to the next activity.) |
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| Rationale of the activity |
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The activity was designed with a
number of considerations in mind. As with most of
the ASCEND activities, there is a focus on group-work.
However, unusually the roles are assigned in this
task. The activity is set up so that the science
specialists are each briefed with some of the information
that is needed to provide a good overview of plant
nutrition (at a suitable level of sophistication
for students studying at GCSE level), and that a
good overall ‘picture’ can be developed by considering
how the specialist knowledge of the biologist, chemist
and physicist may be related. This approach reflects
a view that students readily compartmentalise their
knowledge. Yet finding the links between topics
(and so developing the overall picture) is both
essential to appreciate the nature of science (which
develops a largely coherent, and mutually supporting
knowledge network), and also the type of activity
that we expect to both challenge and motivate the
most able.
The choice of topic is also significant. ASCEND
set out not to simply repeat or preview standard
school fare, and yet the topic of plant nutrition
is a staple of school science. Yet the author’s
personal conversations with GCSE students, including
the more able ones, had revealed that students may
often be able to readily ‘describe’ photosynthesis
and offer formulae for this process and respiration,
without having an overview of the roles (and relationship)
of these key processes. This suggested that the
present activity would not simply be a reinforcement
or preview of a school topic, but would offer a
chance to integrate understanding of photosynthesis
into an extended network of key ideas, linking ideas
about (for example) energy conservation, chemical
change and cellular processes.
Each subject specialist is given a list of points
that may be relevant to the group’s task. So the
biologist’s briefing sheet includes the points that
“in multi-cellular organisms, each cell needs energy
to support its own internal processes”; “cellular
processes occur all the time, so cells need to keep
respiring or they die”; “many, but not all, plant
cells contain organelles called chloroplasts”; “the
arrangement of cells in a leaf often provides gaps
between cells, like a ‘spongy’ structure”. The chemist’s
briefing includes: “energy is released when bonds
are formed during chemical reactions”; “glucose
is soluble in water”; “glucose can be converted
into a polymer called starch”; “many salts, such
as nitrates, dissolve in water” etc. The physicist’s
briefing includes points such as “energy may seem
to change its form, the total amount is constant”;
“solar radiation includes infra-red, visible and
ultra-violet radiation”; “materials are coloured
because they absorb some frequencies of visible
radiation and reflect others”; “diffusion occurs
in gas mixtures and solutions, from a high concentration
to a lower concentration”, etc.
The project manager’s brief provides criteria for
a ‘good’ poster – that it will explain: |
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why roots often spread out into the soil
• why leaves are green
• why leaves have spongy tissue
• why leaves have pores
• why the stomata are usually only on the
underside of the leaves
• why leaves are often supported on stems,
and spread out in different directions
• why some plants have underground stores
of starch |
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These points have been
included to help ensure that students attempt to
draw upon the ideas from biology, chemistry and
physics that are included on the briefing sheets
provided for the team specialists.
The students are also asked to ensure the poster
provides information at a cellular level: that the
“poster should make it clear how individual
cells throughout the plant get their supply
of carbon, nitrogen and energy”. Working at both
the whole plant and cellular level can be challenging,
but is just the kind of task that gifted learners
should respond to (see Chapter 2).
The activity certainly supports outcomes at various
levels. The information provided encourages students
to extend their explanation of plant nutrition to
include such matters as nitrogen uptake, transport
and incorporation into tissues, and magnesium uptake
for synthesising the chlorophyll, as well as consideration
of the sources of the reactants in respiration and
photosynthesis.
The set-up of the activity itself also has two additional
components. Working as a ‘project team’ offers a
very simple reflection of the way scientists often
do work, in teams where different individuals bring
specialist knowledge and skills. The task was also
contextualised in terms of the need of scientists
to communicate their ideas clearly to the public
(the Institute Director’s memo tells the team that
s/he has “decided to form the Conceptual Synthesis
Project to help explain plants, and aspects
of plant science, to the public” – something taken
further in the following activity (Activity 8).
The outcome of this activity, a poster modelling
a complex process, was similar to that undertaken
in Activity 3, potentially offering some reinforcement
of modelling skills used then; and took the form
of an extended and complex explanation: building
on the work in ASCEND Activity 4 (Explaining Science). |
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Figure 7.1:
Modelling plant nutrition, from an integrated (biological
+ chemical + physical) perspective. |
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| Resources |
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| The following resources
are included on the CD: |
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| Resource |
Description |
Filename |
| Introduction |
Memo from the director
of the SynBot Institute for Plant
Sciences to all members of project
teams. |
Act
7 memo |
| Project briefs |
Briefing sheets
for project manager *, project
team biologist, project team chemists,
and project team physicist |
Act
7 briefs |
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Each group will
also need poster paper and drawing materials, and
ideally coloured card/paper, scissors, glue, etc.
*Note: project leader’s briefing sheet invites her/him
to proceed to Activity 8 once the poster is completed.
This instruction should be omitted if the groups
are not to move on to that activity. |
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| Download
PDF of activity 7 brief |
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