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A few primary teachers will have completed some post 16
study or even have a degree in biology, and about half of
the secondary science teachers will have a degree with some
biology content. However that means that a substantial
number of trainee teachers of both primary and secondary
phases will have an understanding of Biology equivalent only
to a grade C at GCSE. The aim of these five ‘biology’
units is to provide support for these trainees (via their
tutors) so that they can either teach to GCSE level, or
acquire an understanding at that level so they have the
confidence to teach at primary school. The emphasis is on
the conceptual changes needed by learners (tutors, teachers
and their pupils) to come to an understanding of living
things.
This unit begins by examining what makes something ‘alive’
and then looks at the place of living things in the
environment. The PowerPoint presentation then provides a
bigger view, looking at the origin of bio-diversity through
evolution.
Although the National Curriculum is constantly changing,
the underlying ideas that we need to introduce children to
are going to remain largely unchanged, though we might need
to change the emphasis and importance we attach to them.
These concepts/ideas are taken from the NC orders 2000 for
KS4 double award and KS3, from section 5 of life processes
and living things:
- habitats support a diversity of plants and animals
that are interdependent (KS3) and how the distribution
and relative abundance of organisms in habitats can be
explained using ideas of interdependence, adaptation,
competition and predation
- the ways in which living things and the
environment can be protected (KS3) and how the impact of
humans on the environment depends on social and economic
factors, including population size, industrial processes
and levels of consumption and waste
- the importance of sustainable development
- some organisms are adapted to survive
daily and seasonal changes in their habitats (KS3)
- predation and competition for resources
affect the size of populations [for example, bacteria,
growth of vegetation] (KS3)
Energy and nutrient transfer
- food chains can be described quantitatively using
pyramids of numbers (KS3) and of biomass (KS4)
- toxic materials can accumulate in food chains.(KS3)
- energy(*) is transferred through an ecosystem
- the role of microbes and other organisms in the
decomposition of organic materials and in the cycling of
carbon and nitrogen
- food production and distribution systems can be
managed to improve the efficiency of energy transfers.
(*) It is biomass that is transferred through an
ecosystem. Some of this (and in some cases less than 10%) is
used for making new biomass and the rest is used as a fuel
for respiration. Energy is associated with the fuel and
oxygen needed for respiration, but it is a confusing short
cut to call this “energy”. This is discussed in more
detail in paragraph 3 below.
The PowerPoint presentation in download 2 explores living
things in their environment from an issues based approach.
Having covered the fundamental conceptual aspects of the
topic (as outlined in the remainder of this unit) this
presentation can be used to progress the trainee teacher’s
thinking within this area. Most slides are accompanied by
explanatory notes which will guide you through the
presentation. It would however be useful to read chapter 7
of Littledyke et al (2000) and the Biodiversity
element of the ‘Science Issues’ CD Rom, before
embarking on the presentation.
Having established what the trainees understand by the
term ‘biodiversity’, the presentation explores a
timeline of events leading to the formation of Earth and
life as we know it. It introduces the significance of
feedback and unpredictability in relation to evolving
systems and, with reference to major environmental changes,
recognises the role of ‘takeover bids’ in establishing
new and stable communities. The focus turns to the
inter-relatedness of the four key components of the Earth
and how they impact one on the other. As members of the
biosphere we too are influenced by changes in the three
remaining components, but we also leave a significant
environmental footprint with practically everything we do.
This impact is explored and discussed in some length towards
the end of the presentation.
Download 3 contains a set of discussion questions that
can be used with trainee teachers, both primary and
secondary, followed by a discussion of the questions
outlining some of the difficulties trainees may encounter in
their subject knowledge.
The final question in this download: “Why is it better to talk of biomass
passing along a food chain than talking of energy
flow?” makes the distinction between matter (made of atoms)
and energy (measured in Joules). In this world of ours it
is matter that gets cycled (never used up) and
these cycles are driven by energy which gets
degraded to waste heat and exported to the universe (for
natural phenomena, such as life and climate the energy
comes mainly, and ultimately from the sun - the rock cycle
is also driven by energy from inside the earth’s
crust.). It is matter that ‘flows’ along food chains -
biomass in fact. If the next organism wants to use some of
this biomass for fuel, then it is respired
(normally involving a reaction where it is joined to
oxygen), and it return to the atmosphere in the form of
carbon dioxide. If it is used for growth it remains as
biomass - available for the next organism on the food
chain (or a detrivores if the biomass drops off as, for
example, shedded skin).
In this section we outline some of the conceptual
barriers to understanding ideas about living things, and
suggest how children’s ideas will develop through their
time in school.
Young children may believe that anything that is active
in any way, including falling or making a noise, is alive.
They tend to think that all things that move, but only
those, are ‘alive’. Even as they get older children may
only refine this belief to all things that move by
themselves, such as rivers and streams, as well as
animals, are alive, but the idea that plants are alive is
hard for them - after all they do not appear to move by
themselves.
Download 3 above warns that children may have a very
limited view of the word ‘plant’ (restricted to
pot plants, not trees, flowers, vegetable crops etc).
The word animal seems to serve a wide function for
very young children - before they learn different categories
(bird, reptile, insect etc). By the time they leave primary
school pupils may have a very narrow view of ‘animal’
using it mostly for mammals only, and in contrast to humans.
As they learn about food chains and webs ‘animal’
gradually begins to stand for all consumer organisms,
including humans.
Some of the main ideas about plants and animals and the
way they interact in their environment are explored in
download 4
K2.5 Download 4: Living things in their environment
The following activities are suitable for outside the
classroom/lab.
Clearly getting trainee teachers out into the environment
- visiting different ecosystems and getting them to
appreciate and identify the variety of living things there -
is essential. See download 3 above. In their turn they will
do the same to their pupils. This simple activity can be
carried out by asking students to examine the trees on the
campus or in their school environment.
Pleurococcus & Lichen distribution to assess
those factors that affect the distribution of different
organisms. http://studentcentral.co.uk/investigating_distribution_pleurococcus_on_trees_tr_8743
These activities can be carried out in the classroom
after samples are collected from the grounds:
Population dynamics of the holly leaf miner
http://www.field-studies-council.org/outdoorclassroom/16plussearch/courseinfo
Investigations with duckweed (Lemna minor)
Estimating the number and biomass of a population of
plants
http://www-saps.plantsci.cam.ac.uk/worksheets/ssheets/ssheet21.htm
The following activities are suitable for the
classroom/lab.
Factors affecting the decay of food. (note the health
and safety points).
Samples of bread can be treated according to the
conditions outlined in Download 5 and placed in sealed
plastic bags. These can be left for two weeks and the
development of decay observed. On health and safety grounds
the bags should not be opened and should be double wrapped
before disposing of with the normal laboratory waste.
Consider trying a variety of processed bread as well as
homemade varieties. How long will ‘value bread’ remain
mould free?
Photosynthesis... using algae wrapped in jelly balls
http://www-saps.plantsci.cam.ac.uk/worksheets/ssheets/ssheet23.htm
- Dickinson, G. and Murphy, K - Ecosystems, London,
Routledge, 1998 (A useful resource for post 16 level work)
- Littledyke, M., Ross, K., and Lakin, L (2000) Science
Knowledge and the Environment, London, David Fulton
(Chapter 7 gives some background information about the major
issues concerning living things in their environment)
- Willaims,G - Techniques and Fieldwork in Ecology, Collins
Educational, 1991 (A general book outlining many skills and procedures for
ecological work at secondary level)
Websites:
- Nature detectives and the
Woodland Trust.
For the Foundation Stage and Key Stages 1 and 2, these
two sites give a colourful and accessible introduction to
environmental issues and activities. They would also be
useful for Key Stage 3.
- The British Ecological Society education pages have a
range of classroom activities and background information
suitable across the key stages.
- The Field Studies Council
(FSC) is an educational
charity committed to bringing environmental understanding to
all. The organisation provides information and opportunities
for people of all ages and abilities to discover, explore,
be inspired by, and understand the natural environment.
Their outdoor classroom pages include information about
suitable activities for use across the key stages and
details about their publications (including their range of
identification keys)
- Science Issues and the National Curriculum. CD Rom
(available from www.glos.ac.uk/science-issues)
Downloads in this Unit:
Section Developed by:
Liz Lakin, St Martin’s College, Ambleside
(and Keith Ross, University of Gloucestershire)
September 2006
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