GCSE Additional Applied Science Teacher guide Topic 4

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Topic 4: Producing Food for the Future
GCSE Additional Applied Science
About the topic
Useful general Websites
In this topic learners:

develop knowledge of the growing global demand for food and that in order to
produce sufficient high quality food to feed the global population, agriculture needs
to make use of scientific progress to improve yields and quality.

develop understanding of the fact that the use of some production techniques has
led to controversy and that this has resulted in the rise of “organic farming”

develop understanding of how science is used to study the nature and production of
foods, the causes of deterioration, the principles of food processing, and the
improvements of foods for the consuming public.
People and regulation
http://www.food.gov.uk/foodindustry/
Prior learning
http://www.beep.ac.uk/content/327.0.html
It is helpful if learners know from KS3 Science
Plants and photosynthesis
Plants for food
Microbes
http://www.yteach.co.uk/index.php/resources/humus_winter_crop_spring_crop_eutrophicatio
n_weed_rhizome_runner_herbicide_crop_rotation_hydroponics_fertilization_eutrophication_
Cultivation_t .html
Health and safety
Risk assessments are required for any hazardous activity.
Model risk assessments used by most employers for normal science activities can be found
in the CLEAPSS Guidance. Teachers need to follow these as indicated in the guidance notes
for the activities, and consider what modifications are needed for individual classroom
situations.
http://www.food.gov.uk/foodindustry/farmingfood/
Food production
http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa/plants/plants1.shtml
http://www.soilassociation.org/LinkClick.aspx?fileticket=nKKZajvOqcI%3D&tabid=280
http://www.ncagr.gov/cyber/kidswrld/plant/nutrient.htm
Food processing
http://www.microbiologyonline.org.uk
http://www.sgm.ac.uk/pubs/micro_today/pdf/020004.pdf
Language for learning
Through the activities in this unit learners will be able to use appropriate scientific and
technical language to clearly communicate their understanding of scientific concepts,
conveying their meaning in a coherent and succinct manner.
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Out-of-school learning
Learners could:

Use websites to review information and consolidate learning:

Investigate organic and non organic foods sold in local supermarkets

Research the nutrient constituents of different fertilisers
Good learning Practice
Learners should be given explicit level statements, using Grade Descriptors, relating to each
activity they undertake. This will enable them to measure and monitor their own performance.
Controlled Assessment
Teachers are advised to build into their teaching programme time to complete controlled
assessment. Controlled assessment activities are changed each year. This will mean that
centres will need to review their scheme of work to ensure that the chosen controlled
assessments are covered at an appropriate time.
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4.1 People and regulation
Learning Objectives
Possible Learning Activities
Learners should
4.1.1 recognise that food production and
agriculture needs to be regulated in order to
protect public safety and maintain animal
welfare.
4.1.2 explain the need for enforcement
officers to monitor the food chain (e.g.
environmental health practitioners and
factory inspectors).
4.1.3 recognise that agriculture and food
scientists are involved in studying crops and
farm animals to improve the quality and
yields. They also may monitor the effect of
various methods of crop production on the
biodiversity of an area.
Resources
Hook Activities:
Involve an expert: a representative from the Food Standards
Agency could be invited in to take on the “mantle of the expert”.
Prior to the visit learners could work in pairs to prepare a set of
questions related to the subject of the regulation of food production
and agriculture. The “expert” could be asked to give a short
presentation (no more than 10 minutes) and then in turn pairs of
learners ask their pre-prepared questions.
Learners could then be set a task by “the expert” to design a leaflet
or poster that explains why food production and agriculture need to
be regulated
http://www.food.gov.uk/wales/aboutus_wales
/
http://www.food.gov.uk/wales/aboutus_wales
/contactus/
Starters:
What’s in our food, where does it come from?? Working in teams
of no more than 3, learners are given a shopping list of 6 items, but
rather than buy the items learners have to find out how the food was
produced/processed, and the source of the main ingredients.
Learners need to complete a given table that indicates the
production/process method and source of main ingredient for each
food item on their list. When the table is completed and the class is
together, each team has to read through their list, describing their
findings and any difficulties they had in finding out information
Research activity Spilt the class into research teams, to investigate
organisations which are responsible for regulation in the food
industry. Using books and the internet the research teams have a
fixed amount of time (say 20 minutes) to find out and report back on
a range of organisations the regulate the food industry, this should
include, but not be limited to: Food Standards Agengy, DEFRA, and
Environmental health practitioners
http://www.defra.gov.uk/corporate/
Main Activities:
Interpreting an article: Read an article on a recent “food scare” to
the class. Discuss as a class the possible sources of contamination
of food in the various stages of production
Ask learners (working in pairs) to draw a flip chart poster that
illustrates how/where contamination may occur in the food chain.
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http://www.bbc.co.uk/news/world-europe13746682
http://www.guardian.co.uk/world/2011/jan/07
/dioxin-alert-eggs-enter-uk-german-farms
Points to note
Flipcharts can then be displayed and shared. Ask learners to add
on to their posters where regulation would occur and who would be
responsible for this regulation. Once completed posters can be
photographed for learner’s files
Leaflet Design: following a presentation by the teacher on
Biodiversity and crop production, learners are asked to design a
leaflet for the Food Standards Agency will help young farmers
understand the importance of preserving biodiversity and how this
can be achieved in farming
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Reviewing work
Learning Objectives
Possible Learning Activities
Learners should learn
Review their knowledge and understanding
of people and regulation
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Matching exercise: provide learners with a list of job tiles and
organisations. Also provide a list of short statements that matches
one of the job titles or one of the organisations. Ask learners
(working individually or in pairs), to match the two lists in a specified
time (max 5 minutes)
Resources
Points to note
4.2 Food production
Learning Objectives
Learners should
Possible Learning Activities
4.2.1 know that as crops grow they remove
essential nutrients from the soil that need to
be replaced (use of artificial fertilisers, soil
dressings and organic sources of nutrients
e.g. manure).
4.2.2 understand that plants need nitrogen,
phosphorous, potassium and magnesium for
healthy growth and the effects of
deficiencies of these nutrients on the plants.
Know that nitrogen is found in chlorophyll;
phosphorous is found in ATP, an enzyme
involved in energy transfer; and potassium is
important in water regulation by controlling
the opening and closing of stoma.
4.2.3 interpret data to show how intensive
farming increases crop yield by using
artificial fertilisers, pesticides, fungicides and
herbicides.
4.2.4 draw and label diagrams of plant cells.
Understand the function of the following
parts: cell membrane, cytoplasm, nucleus;
plus cell wall, chloroplast, vacuole.
4.2.5 understand the importance of
photosynthesis whereby green plants and
other photosynthetic organisms use
chlorophyll to absorb light energy and
convert carbon dioxide and water into
glucose, producing oxygen as a by-product.
The chemical reactions of photosynthesis
within the cell are controlled by enzymes.
Know the word equation for photosynthesis.
(Details of the enzymes involved in
photosynthesis are not required.)
4.2.6 explain how intensive farming
increases food production by using
controlled environments. Controlled
environments allow the management of
conditions such as temperature, light and
ventilation and the amount of carbon dioxide
that is available for photosynthesis in plants.
4.2.7 know that fertilisers are water soluble
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Farm visit: arrange for learners to visit an arable farm to see first
hand the production methods used, the farms policy on use of
fertilisers and pesticides etc,. Visits to two different farms, one using
mostly intensive methods and one using organic methods would be
of great benefit if possible to arrange this.
Resources
http://www.defra.gov.uk/environment/natural/
biodiversity/
Horticultural nursery visit. Arrange for learners to visit a large
scale nursery operation (many local councils have their own
nurseries, or a commercial organisation). The control of the
environment to encourage the process of photosynthesis could be
highlighted on such a visit
Starters:
Research activities
1) Advantages and disadvantages of intensive farming and
organic farming: spilt learners into research teams to carry out
investigations into the advantages and disadvantages of intensive
farming or the advantages and disadvantages of organic farming..
Each research team should then give a 5 minute overview of their
findings
http://en.wikipedia.org/wiki/Intensive_farming
http://www.buzzle.com/articles/advantagesand-disadvantages-for-intensivefarming.html
http://www.organic-store.co.uk/organicfarms.html
2) What’s the alternative? Explain to learners that biological control
of pests is an alternative to the use of pesticides. Research teams
now need to identify at least 2 real life examples of biological control
and then list the advantages and disadvantages of biological control
(if learners struggle with this task, the teacher could provide two
examples to help with identifying advantages and disadvantages,
good examples to use would be: ladybirds to kill aphids and
Myxomatosis virus to kill rabbits)
Main Activities:
http://www.bbc.co.uk/schools/gcsebitesize/s
cience/add_gateway/chemical/fertilisersrev1.
shtml
Data investigations: Learners are provided with data that forms a
“case study” of a particular farm. They need to interpret this data to
comment how yield has increased over a period of time, and how
much fertiliser has also been used. Different teams of learners
could be presented with different data, which they could then join
together to discuss. Data should also be provided on measures of
http://www.besy.org.uk/Doncaster/SCIENCE%20%20Leaf%20T5AgroBiology%20science%20
broad%20.pdf
http://en.wikipedia.org/wiki/Biological_pest_c
ontrol
http://en.wikipedia.org/wiki/Myxomatosis
Points to note
and some fertilisers can be prepared by
neutralisation reactions (e.g. ammonium
sulphate).
4.2.8 describe how organic farming keeps
animals under more natural conditions and
that alternative methods are used in crop
production such as the use of natural
pesticides and natural fertilizers, and
mechanical methods of eliminating weeds.
4.2.9 discuss the advantages and
disadvantages of organic and intensive
farming (food quality, cost, animal welfare,
crop yields, effect on environment, public
opinion and awareness).
4.2.10 understand the difference between
selective breeding and genetic modification.
Genetic modification also allows the genes
from an unrelated organism to be
transferred. The new organism with the
inserted genes has the genetic information
for one or more new characteristics.
Selective breeding is the process of
breeding the animals with the characteristics
you want with other animals with those
characteristics to produce more animals with
good characteristics over many generations.
4.2.11 discuss the advantages and
disadvantages of selective breeding and the
use of GM in the food industry.
4.2.12 assess how crop growth is affected
by factors such as plant density, light levels
and the use of fertilisers.
4.2.13 understand what is meant by
biodiversity, the variety or number of
different species in an area, and why it is
important. Understand the need for and
issues associated with the collection of
reliable data and ongoing environmental
monitoring. Appreciate how mathematical
modelling can be used to analyse
environmental interactions and predict
trends.
4.2.14 understand the principles of
sampling, the need to collect sufficient data
and use of appropriate statistical analysis.
(Details of statistical tests are not required.)
4.2.15 use quadrats to investigate the
abundance of species.
4.2.16 understand how farming methods can
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biodiversity on the farm as crop production methods have changed.
Learners can then interpret this data to assess the impact of
different crop production methods on the farm. Learners should
also be asked to comment on the validity of the data.
Practical activities
Effect of deficiencies of N,P and K on plant growth and
development
Using test tubes containing 5 different water cultures: one with all
nutrients in, one with all nutrients except Nitrate, one with all
nutrients except Potassium, one with all nutrients except
Phosphorus, and one final tube containing just distilled water (i.e.
no mineral elements at all). Using 5 seedlings which all appear to
be at the same stage of development, place a seedling in each test
tube, so that the root is covered by culture solution. Using wheat
seedlings works well with a strip of cotton wool around the grain to
hold it in place in the test tube but leaves root and shoot free.
Seedlings need to be left for two weeks, but water level will need
topping up in each tube regularly (and very carefully) each with
distilled water only. After two weeks various measurements and
observations can be made: leaf colour, leaf length, total root length
and weight,
How intensity of light affects the rate of photosynthesis. Using
pondweed and varying light intensities, the rate of photosynthesis is
measured by the amount of bubbles (oxygen) given off from the cut
end of the piece of pondweed. Light intensity can easily be altered
by varying the distance a light source is from the beaker containing
the pondweed. The water the pondweed is submerged in must have
be a suitable concentration of sodium carbonate, to ensure there is
enough Carbon Dioxide for photosynthesis to take place
From field to food. Explain to learners that a field which is currently
left uncultivated is about to be used for crop growth. They have
been asked to investigate how this could affect the biodiversity of
the area. Using standard sampling techniques, transects, quadrats
and pooters etc.. Learners work in teams to identify organisms. All
the data collected is then combined back in class and there is a
discussion about how organisms may be affected if crops are
grown. Working in pairs learners are then asked to write an e-mail
to the local planning office about the effect of changing the use of
the field. Any filed, including one in the school grounds could be
used for this activity, if a filed near a farm was accessible, this
would obviously make the practical activity more realistic.
http://www.field-studiescouncil.org/outdoorscience/diy.htm
impact on biodiversity (e.g. use of
pesticides, fertilisers and land drainage).
Interpret data to assess the impact of
different methods of crop production on
biodiversity.
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Research and debate activity: World food supplies and GM
(genetically modified foods). Following a presentation from the
teacher which recaps on genetics. Learners are split into research
teams to find the facts. They need to answer the following
questions: How does plant breeding help in the production of crops?
What are GM foods? Does the world have enough food to feed its
population? What concerns do people have about GM foods?
Research teams are now allocated into one of three categories:
a)“for” GM foods, b) “against” GM foods, c) the deciders . Those
allocated into a or b must now use the information they obtained to
make a convincing argument, those allocated into c must decide
who is the most convincing and why
lhttp://www.channel4learning.com/support/pr
ogrammenotes/micro/farmrevealed/prog1.ht
ml
Reviewing work
Learning Objectives
Possible Learning Activities
Learners should
Review their knowledge and understanding
of food production
Bingo: Ask learners to draw quickly a blank nine square “bingo” grid.
Teacher writes on the white board 12 key terms related to food
production topic, such as: Biodiversity, pesticides. Chlorophyll,
intensive farming etc... Learners choose 9 of these terms and write
them into their squares. Start the “game” by reading the first
definition of one of the 12 terms and continue in a random order.
Learners’ mark of their “card” when the definition read out matches a
term they have written on their card. Learners can call out when they
have a “line” and they read back both the terms and definitions. The
“game” can continue until someone has a full house
Reviewing a website: provide learners with a particular website
(such as the one given here). Explain that they are a website
reviewer, they need to work through the web based activity and
comment on what is good about the activity, who could use it, how it
could be improved. Learners could work individually on this task or in
pairs, different pairs could review different website activities
GCSE Additional Applied Science
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Resources
http://www.bbc.co.uk/schools/gcsebitesize/sci
ence/add_aqa/plants/plants1.shtml
http://www.bbc.co.uk/schools/gcsebitesize/sci
ence/21c/food/farmingmethodsact.shtml
Points to note
4.3 Food processing
Learning Objectives
Possible Learning Activities
Learners should
4.3.1 be able to describe the use of bacteria,
yeast, and other fungi in food production
(bread, wine, beer, yoghurt and cheese).
4.3.2 understand the different stages in the
processing of yoghurt, cheese and beer.
Interpret information on yoghurt, cheese and
beer production.
4.3.3 know the optimum conditions for the
growth of bacteria (suitable temperature,
moisture, and food source) and the
significance of this in food production.
4.3.4 explain why non-homogenised milk
separates into two layers.
4.3.5 describe how milk can be
homogenised. This is achieved by pumping
milk at high pressure through narrow tubes
and explains how this affects the size of fat
globules in milk resulting in an emulsion.
4.3.6 understand that food spoilage occurs.
It may be accelerated by storage conditions
and is often due to bacterial and fungal
action.
4.3.7 explain different ways in which the
growth of bacteria is slowed down or
stopped (refrigeration, freezing, heating,
drying, salting, smoking, pickling (lowering
pH)).
4.3.8 understand that pasteurisation is a
process which slows microbial growth in
food and recognise that it can be used to
treat a number of foods including beer, milk
and fruit juice.
4.3.9 understand that milk is pasteurised by
heating sufficiently to kill some pathogens.
This does not sterilise the milk since the
food will still deteriorate with time.
4.3.10 understand how food preparation
areas are kept free of bacteria (personal
hygiene, disinfectants, detergents,
sterilisation, disposal of waste, control of
pests e.g. insects, mice and rats).
4.3.11 explain how cross contamination of
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Resources
Hook Activities:
Food production visit: arrange for learners to visit a food
production company to see the production of yoghurt, cheese or
beer first hand. This could be linked to talks by various employees
on how the a particular product is produced .
(from field to fridge)
http://www.ukagriculture.com/field_to_fridge/
field_to_fridge.cfm?strcategory=Milk%20Pro
duction&strdate=5.00am&intro=no
On screen production techniques Pull together a range of online/video clips which all contain examples of food production
techniques. Using only a few seconds of each clip to produce a
montage. Show the montage and ask learners to identify as many
foods being produced as they can
http://www.youtube.com/watch?v=6vBBW1v
uJEk&feature=related
http://www.foodafactoflife.org.uk/VideoActivit
y.aspx?contentId=163&sectionId=63&siteId=
14&titleId=171
http://www.world-of-cheese.com/cheesemaking/videos.htm
Starters:
Converting information. Provide learners with text wihich describe
the different stages in the processing of yoghurt, cheese and beer
production. Working in pairs and using flip chart paper, ask learners
to convert this information into a flow chart
How should it be stored—practical activity? Using a (fairly ripe)
soft fruit such as plums or pears, discuss with learners how these
should be stored? Ask learners to come up with a way to test
different storage conditions, ask them to think about temperature,
moisture, light etc... Leave fruit in different conditions for a week,
observe as a class changes in the fruit. Ask learners what has
caused the fruit to spoil? Which condition was best for keeping
the fruit from spoiling?
Main Activities:
Resource station research: set up resource stations around the
room, which contain a range of information about the different ways
in which the growth of bacteria can be slowed down. The
information provided at each resource station should be varied—i.e.
pages of text, a short video, an audio cassette, website pages.
http://www.biotopics.co.uk/edexcel/biotechno
l/yog.html
http://www.world-of-cheese.com/cheesemaking.htm
Points to note
food can be prevented.
4.3.12 know that food poisoning is caused
by the growth of microorganisms, usually
bacteria, and by the toxins they produce
when they grow.
4.3.13 give examples of bacteria that cause
food poisoning (Campylobacter sp., E.coli,
Salmonella sp.) and know the common
symptoms for food poisoning (stomach
pains, vomiting, and diarrhoea).
4.3.14 interpret data on the growth of
microorganism (colony counts, turbidity).
4.3.15 discuss the potential impact of the
contamination of food products, with
bacteria (e.g. by commercial food
preparation outlets).
Working in groups of 5, the group has to decide which member of
the group to send to each resource station. Within a fixed time limit
each learner must make notes about the information at the resource
station. Learners from different groups will need to work together at
each resource station. Learners then return to their own “home
group” and take it in turns to explain what they learnt at their
resource station.
Food contamination: A local hotel has asked for help in explaining
to new kitchen staff how food preparation areas can be kept free of
bacteria. The hotel would like the leaflet to include information on
the fact that food poisoning is often caused by bacteria in food. The
leaflet needs to include information on personal hygiene,
disinfectants, detergents, sterilisation, and disposal of waste and
cross contamination.
. Learners could each produce individual leaflets and then compare
and select “the best” or this could be a team activity Alternatively a
local hotel manger could be invited to judge the leaflets and select
the best one
Causes of food poisoning Make a set of cards for learners; with
each card noting the name of a particular bacterium that can cause
food poisoning if possible include an electron microscope
photograph of the bacteria on the card. Ask pairs of learners to
select three cards each. Using books and the internet ask each pair
to find out the following information about each bacteria on their
cards:
What disease can the micro-organism cause?
What are the symptoms of the disease?
Can the disease be treated?
Findings can then be shared in class, cards could be displayed on
classroom walls
Practical activities to investigate the growth of microorganisms: There are numerous microbiology practical activities
that could be undertaken. These include
a)Finger plate tests on the effect of antibacterial hand washes (this
could be linked to the food contamination leaflet activity above, by
setting this in a hotel kitchen scenario)
b)Altering conditions for growth, temperature, ph of growth medium
etc. and analysing growth by colony count or turbidity
c)Effect of different disinfectants by using paper discs soaked in c)
different disinfectants (or different strengths of disinfectant)
d) testing the freshness of different milk samples
GCSE Additional Applied Science
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http://www.sparsholtschoolscentre.org.uk/teac
hers/resources/secondary/milk_micro_lab.p
df
http://www.biotopics.co.uk/edexcel/pracw.html
Reviewing work
Learning Objectives
Possible Learning Activities
Learners should
Review their knowledge and understanding
of food processing
Memory board: write down a number of terms related to the topic of
food processing (pasteurisation, sterilisation, colony counts, bacteria,
toxins, disinfectants etc....). Give learners a minute or so to
remember the terms (but not to write them down). As soon as the
time is up rub the terms off the board, now ask the students to write
down, not the terms themselves, but the definition/explanation of the
term. Again give only a specified time to do this then go over each
term and discuss the different ways in which learners have
defined/explained them ,
Go large exam questions: Write out an exam style questions on the
topic of micro-organism growth at the top of a flipchart sheets. Put
these sheets on desk around the class room. Allocate pairs of
learners to a particular question sheet. At the word “go” the pair
makes a start to answer the question they have been allocated to, at
the word “move” learners then move to another question. There
needs to be more questions then pairs of students, as only one pair
is allowed at a question sheet at anyone time. When at the second
and subsequent question sheets, learners need to read the previous
answer, add to this or make corrections to any incorrect information.
At the end of the activity (say up to 5 “moves”) learners return to their
original questions, review and mark the answer that has been
provided. .
GCSE Additional Applied Science
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Resources
Points to note
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