Download Examples in Context - Biology

Examples in Context - Biology
Unit 1
Biodiversity
Technology as a tool to measure, analyse and monitor biodiversity
Developments in software, computing and supercomputing have been important in ecological
classification as they have enabled scientists to classify regions according to large sets of biotic and
abiotic data and to compare data over time (ACSBL010). Supercomputers have also enabled the
development of large, complex models to analyse species data collected from multiple individuals
in a range of locations, and to infer relationships between species, including their shared
evolutionary past (ACSBL009). Advances in remote sensing radar imagery and satellite tracking in
real time have enabled scientists to measure and monitor populations and play a significant role in
surveying and monitoring large or inaccessible ecosystems.
Science as a Human Endeavour links
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Development of complex models and/or theories often requires a wide range of evidence
from multiple individuals and across disciplines (ACSBL009)
Advances in science understanding in one field can influence other areas of science,
technology and engineering (ACSBL010)
International biodiversity protection
International agreements about biodiversity protection, such as the World Heritage Convention,
are based on the premise that local, regional and international biodiversity represent a global
resource, vital for human survival, that should be maintained for future generations (ACSBL008).
The World Heritage Convention is designed to ensure the protection of natural and cultural
heritage and encourage international cooperation in the conservation of biodiversity. Sites are
selected as natural World Heritage based on a range of criteria, including, but not limited to,
conservation of biodiversity (ACSBL011). Selected sites are monitored to ensure continued
integrity, protection and management, including evaluation of projected economic, social and
environmental impacts on the site (ACSBL014). Within the international scientific community,
methods and findings related to biodiversity monitoring and analysis are shared through peer
reviewed articles in international journals (ACSBL014).
Science as a Human Endeavour links
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Science is a global enterprise that relies on clear communication, international conventions,
peer review and reproducibility (ACSBL008)
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The use of scientific knowledge is influenced by social, economic, cultural and ethical
considerations (ACSBL011)
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Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL014)
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Biodiversity targets
Setting agreed biodiversity targets has been proposed as one way to achieve positive international
action towards biodiversity conservation and encourage accountability (ACSBL008). Setting such
targets requires a broad range of scientific knowledge in gathering data, identifying indicators and
ensuring that measurement is valid and reliable and will inform improved ecosystem management
(ACSBL009). The 2010 Biodiversity Target was endorsed by the World Summit on Sustainable
Development and aimed to achieve a significant reduction in the rate of biodiversity loss at global,
regional and national levels. Measurement of attainment of this target required international
agreement regarding baseline data, acceptable timescales, acceptable rates and appropriate
measures for monitoring and evaluating the rate of biodiversity loss (ACSBL008).
Science as a Human Endeavour links
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Science is a global enterprise that relies on clear communication, international conventions,
peer review and reproducibility (ACSBL008)
Development of complex models and/or theories often requires a wide range of evidence
from multiple individuals and across disciplines (ACSBL009)
Ecosystem dynamics
Indigenous knowledge of ecosystem interactions and change
Indigenous knowledge of environmental change and interactions between abiotic and biotic
elements of ecosystems in local contexts has developed over thousands of years and provides
valuable data for understanding ecosystem dynamics (ACSBL009). Some Indigenous knowledge is
represented in Indigenous art and can include evidence of past biodiversity and climate change that
supports data from the fossil record. Indigenous knowledge also includes land management
practices that can maintain ecosystems at specific successional points. These practices are often
used to complement practices in conservation areas, where land management decisions reflect
scientific, social, cultural and ethical considerations (ACSBL011).
Science as a Human Endeavour links
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Development of complex models and/or theories often requires a wide range of evidence
from multiple individuals and across disciplines (ACSBL009)
The use of scientific knowledge is influenced by social, economic, cultural and ethical
considerations (ACSBL011)
Marine reserves
Southeast Asia is a global epicentre for marine diversity; the establishment of marine reserves aims
to contribute to the long-term conservation of marine ecosystems and protect marine biodiversity.
Identification and classification of marine reserve areas requires consideration of enforcement
logistics, the multiple uses of the area (for example, fishing, recreation, tourism), indigenous
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peoples’ usage rights, and the extent of the area required to contribute to local and global
biodiversity conservation (ACSBL011). Scientific knowledge based on local data collection and
analysis, computer simulation of future scenarios and analysis of analogous scenarios is required to
analyse these factors, classify areas and predict the likelihood that the reserve will successfully
protect marine biodiversity (ACSBL013).
Science as a Human Endeavour links
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The use of scientific knowledge is influenced by social, economic, cultural and ethical
considerations (ACSBL011)
Scientific knowledge can enable scientists to offer valid explanations and make reliable
predictions (ACSBL013)
Keystone species and conservation
The concept of a keystone species, a species that is particularly important in maintaining the
structure of an ecological community, was first introduced by Robert T Paine in the late 1960s. Data
supporting the theory has been collected by a large number of scientists from across a wide range
of ecosystems and for a wide range of species (ACSBL009). Some biologists have advocated for
keystone species to be special targets for conservation efforts and keystone species theory has
informed many conservation strategies. However there are differing views about the effectiveness
of single-species conservation (such as keystone species, flagship species or umbrella species) in
maintaining complex ecosystem dynamics (ACSBL012).
Science as a Human Endeavour links
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The use of scientific knowledge may have beneficial and/or harmful and/or unintended
consequences (ACSBL012)
Development of complex models and/or theories often requires a wide range of evidence
from multiple individuals and across disciplines (ACSBL009)
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Unit 2
Cells as the basis of life
Stem cell research
Embryonic stem cells have the potential to be grown into specialised cells and could enable the
repair or replacement of ailing organs and tissues. In the late 1990s, stem cells were successfully
removed from available embryos at fertility clinics and the world’s first embryonic stem cell line
was established (ACSBL037), prompting excitement in the international scientific community and
concern in religious and political circles. Concerns about the potential for unethical human
experimentation has prompted some governments to prohibit some types of stem cell research, or
to limit government funding for it (ACSBL040). International groups such as the International
Society for Stem Cell Research have convened experts in science, ethics and law to develop
guidelines for human embryonic stem cell research, with the aim of promoting transparent and
uniform practice worldwide (ACSBL037).
Science as a Human Endeavour links
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Science is a global enterprise that relies on clear communication, international conventions,
peer review and reproducibility (ACSBL037)
The use of scientific knowledge is influenced by social, economic, cultural and ethical
considerations (ACSBL040)
Photosynthesis and productivity
Photosynthesis is one of the most important biological processes on Earth but it is quite inefficient;
researchers report that natural trade-offs result in very low efficiency in many important food
crops. Research is currently underway to engineer or enhance photosynthesis to improve food and
fuel production. This includes the development of artificial leaves that convert solar energy to a
liquid fuel via a process similar to photosynthesis, and investigation of combining more efficient
algal photosynthesis with plant photosynthesis to improve crop productivity (ACSBL041). These
advances have the potential to decrease reliance of fossil fuels and improve agricultural
sustainability (ACSBL043).
Science as a Human Endeavour links
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The use of scientific knowledge may have beneficial and/or harmful and/or unintended
consequences (ACSBL041)
Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL043)
Cell membrane model development
From the nineteenth century it was accepted that some form of semi-permeable barrier must exist
around a cell, although there was no evidence to indicate its structure. Various scientists, including
Traube, Quincke, Fricke and Gorter and Grendel, contributed to the theory that the cell membrane
was composed of a lipid bilayer, and in the 1950s the use of electron microscopy confirmed these
results through direct investigation of the membrane (ACSBL039). The first model of the membrane
to incorporate the notion of fluidity was proposed by Mueller and Rudin in the 1960s, and it was
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demonstrated conclusively by Frye and Edidin in 1970. The results of this experiment were used by
Singer and Nicolson as evidence for their 1972 proposal of the fluid mosaic model of the cell
membrane (ACSBL038). Ongoing research continues to refine this model, such as research into the
structure of channel proteins in the membrane (ACSBL038).
Science as a Human Endeavour links
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Development of complex models and/or theories often requires a wide range of evidence
from multiple individuals and across disciplines (ACSBL038)
Advances in science understanding in one field can influence other areas of science,
technology and engineering (ACSBL039)
Multicellular organisms
Animal ethics
The use of animals in research has played an important role in furthering scientific understanding of
the structure and function of multicellular organisms and the mechanisms of medical interventions.
Ethical treatment of animals as sentient, feeling beings has been accepted as a global principle in
research and the three strategies of replacement, reduction and refinement form the basis of many
international guidelines (ACSBL037). Replacement is defined as the substitution for conscious living
higher animals of insentient material, such as through use of tissue culture techniques; reduction
involves using only the minimum number of animals needed to meet statistical requirements; and
refinement involves decreasing the severity of the impact of the procedure on any animals that
have to be used. These strategies are based on scientific research and have been devised to inform
sustainable ethical use of animals in research (ACSBL043).
Science as a Human Endeavour links
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Science is a global enterprise that relies on clear communication, international conventions,
peer review and reproducibility (ACSBL037)
Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL043)
Organ and tissue transplantation
Modern surgical techniques have made it possible for diseased or damaged organs to be replaced
by healthy ones from a living or dead donor. Improvements in technologies to store and transport
living tissue and the development of immunosuppressive drugs to decrease rejection by transplant
recipients have led to increasing numbers of people benefiting from organ and tissue transplants
(ACSBL039). However the increased demand for transplantation has also led to illegal organ and
tissue trafficking, forced donation and ‘transplantation tourism’, where individuals travel to other
countries where it is easier or cheaper to obtain a transplant. These situations may involve violation
of human rights and exploitation of the poor, and pose many ethical concerns (ACSBL041).
Science as a Human Endeavour links
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The use of scientific knowledge may have beneficial and/or harmful and/or unintended
consequences (ACSBL041)
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Advances in science understanding in one field can influence other areas of science,
technology and engineering (ACSBL039)
Bioartificial organs
There is a demand for bioartificial tissues and organs as an alternative to donor organs or tissues,
which are in short supply and may be rejected by the recipient’s body (ACSBL040). To design
bioartificial organs, scientists use knowledge of the structure and function of organs to design a
scaffold and populate it with functional tissue. Healthy cells from the patient’s diseased organ are
extracted and grown on the scaffold, with cells applied in layers to encourage them to form tissues.
If the patient’s own cells are too badly damaged, organs could be grown using cells from a stem cell
bank. Developments in this area could lead to a future in which surgeons would order organs to be
grown as needed, removing the need to wait for donors whose organs and tissues might not be a
perfect match to the recipient (ACSBL042).
Science as a Human Endeavour links
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The use of scientific knowledge is influenced by social, economic, cultural and ethical
considerations (ACSBL040)
Scientific knowledge can enable scientists to offer valid explanations and make reliable
predictions (ACSBL042)
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Unit 3
DNA, genes and the continuity of life
Bioinformatics
Bioinformatics involves the construction, maintenance and use of databases to analyse the
relationships in biological data, such as amino acid sequences or nucleotide sequences (ACSBL068).
DNA and protein sequences can be mapped and analysed to compare genes within a species or
between different species. One example of a bioinformatics project is the Human Genome Project,
an international, collaborative research project which resulted in the publication of the full
sequence of the human genome in 2003 (ACSBL073). The project was completed ahead of
schedule, largely as a result of widespread international cooperation and advances in genomics and
computing. The databases associated with the project are freely available via the internet, and this
data is used extensively by the international scientific community.
Science as a Human Endeavour links
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ICT and other technologies have dramatically increased the size, accuracy and geographic
and temporal scope of data sets with which scientists work (ACSBL068)
International collaboration is often required when investing in large-scale science projects
or addressing issues for the Asia-Pacific region (ACSBL073)
A $1000 genome
A number of companies have announced that individuals will soon be able to access full genome
sequencing for roughly $1000, enabling many more people to identify whether they have gene
variants associated with genetic disease (ACSBL071). One potential application of this technology is
the sequencing of all babies at birth, in order to enable doctors to identify genetic conditions and
structure individualised healthcare, dietary and exercise regimes that will lead to better health.
However there is significant concern about the risks in making this data so readily available, and the
privacy issues regarding ownership and availability of sequences. Many groups are calling for
safeguards to be implemented before whole genome sequencing becomes widespread, including
legislation to protect personal privacy, regardless of how the sample was obtained (ACSBL070).
Science as a Human Endeavour links
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People can use scientific knowledge to inform the monitoring, assessment and evaluation
of risk (ACSBL071)
The acceptance of scientific knowledge can be influenced by the social, economic, and
cultural context in which it is considered (ACSBL070)
Genetically modified organisms
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Genetic engineering to insert genes responsible for specific traits into plant and animal DNA is seen
by some scientists as the next wave of advancement in agriculture, with the potential to increase
crop yields and provide ways to grow crops on degraded lands (ACSBL074). A wide range of
transgenic crops is currently on the market, some having been engineered to resist pesticides,
insects and disease. Work is also underway on transgenic animals with engineered traits such as
faster growth and the ability to produce pharmaceuticals. Critics fear that genetically engineered
products are being rushed to market before their effects are fully understood. Concerns include
possible health risks to consumers and the long term ecological impact of releasing engineered
organisms into the environment, including the effects on non-target organisms, a speeding of the
evolution of pesticide-resistant pest species, and the possibility of gene flow from crop species to
weed species resulting in the emergence of ‘super weeds’ (ACSBL072).
Science as a Human Endeavour links
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Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL074)
Science can be limited in its ability to provide definitive answers to public debate; there
may be insufficient reliable data available, or interpretation of the data may be open to
question (ACSBL072)
Continuity of life on Earth
Evidence for evolution
Darwin proposed the theory of evolution by natural selection to refute Lamarck’s theory. He
provided evidence for descent with modification (branching evolution) based on patterns in
variation of domesticated and wild species, and patterns of species distributions in time and space
(ACSBL069). Contemporary evidence for evolution comes from five main lines of evidence:
paleontology, biogeography, developmental biology, morphology and genetics. Technological
developments in the fields of comparative genomics, comparative biochemistry and bioinformatics
have enabled identification of further evidence for evolutionary relationships (ACSBL068).
Science as a Human Endeavour links
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ICT and other technologies have dramatically increased the size, accuracy and geographic
and temporal scope of data sets with which scientists work (ACSBL068)
Models and theories are contested and refined or replaced when new evidence challenges
them, or when a new model or theory has greater explanatory power (ACSBL069)
Human evolution – are we still evolving?
Theoretical models of natural selection do not account for culture and technology, which can alter
selection pressures so that it is not necessarily the ‘fittest’ that survive to reproduce. This has
caused some to ask whether human evolution is still occurring, particularly in Western societies
post the significant cultural events of agriculture, the Industrial Revolution, modern medicine and
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mass transportation. However, new results from projects such as the 1000 Genomes Project
indicate that the rapid increase in the human population (from roughly five million at the end of the
last Ice Age to more than seven billion today) has generated an enormous amount of variation in
the species (ACSBL068). Other localised studies point to fertility-related natural selection
(ACSBL069).
Science as a Human Endeavour links
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Models and theories are contested and refined or replaced when new evidence challenges
them, or when a new model or theory has greater explanatory power (ACSBL069)
ICT and other technologies have dramatically increased the size, accuracy and geographic
and temporal scope of data sets with which scientists work (ACSBL068)
Sustainable population size and reserve area
The notion of minimum reserve size to maintain ecological processes is an important focus of
conservation planning, and includes consideration of biogeography and population dynamics.
Estimating minimum reserve size for a target conservation species can involve the calculation of
minimum viable population and consideration of the area required for each individual in that
population, given species preferences for particular habitat and social dynamics within the
population (ACSBL074). However, determination of reserve size must also consider the needs and
attitudes of other stakeholders, including cultural and economic values of indigenous peoples,
recreational and aesthetic values of the public, the capacity to protect, monitor and manage the
reserve, and other factors (ACSBL070). An alternative to single large reserves may be a number of
smaller reserves that are connected by ‘green corridors’ that enable fauna to migrate.
Science as a Human Endeavour links
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The acceptance of scientific knowledge can be influenced by the social, economic, and
cultural context in which it is considered (ACSBL070)
Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL074)
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Unit 4
Homeostasis
Modeling human thermoregulation
Computer models of human thermoregulation responses, including heat transfer, perspiration,
respiration and blood flows, have been developed for use in the design of clothing and
environments that aim to protect humans from hyper- and hypothermia (ACSBL103). Models of
human thermoregulation can aid in the design of military chemical suits, industrial protective
clothing, space suits, and environments such as space stations, aircraft, vehicles and buildings.
Simulating and modeling the human thermoregulatory system also enable scientists to study and
predict the effects of extreme environments on the human body, and to design safety regulations
for people working in these environments, such as firefighters, pilots, foundry workers and soldiers
(ACSBL106).
Science as a Human Endeavour links
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ICT and other technologies have dramatically increased the size, accuracy and geographic
and temporal scope of data sets with which scientists work (ACSBL103)
People can use scientific knowledge to inform the monitoring, assessment and evaluation
of risk (ACSBL106)
Use of hormones in the dairy industry
Use of growth hormones and other hormones is controversial in the livestock industry, with
proponents arguing that they increase productivity, reduce the cost of production and improve
food affordability. Recombinant bovine somatotropin (rBST) is a synthetically produced hormone
that has been shown to increase milk yield. While proponents of rBST point to studies that show
that milk products produced using rBST cannot be distinguished from other milk products, the
Codex Alimentarius Commission, a United Nations body that sets international food standards, has
to date refused to approve rBST as safe (ACSBL107). While the United States and other countries
currently allow the use of rBST, countries such as Australia and New Zealand have banned it based
on evidence that it increases the risk of health issues in cows and because of concerns regarding
milk contamination (ACSBL106). This issue is significant in international trade of dairy products,
prompting debate about appropriate labeling of milk products, international standards and
reasonable import bans.
Science as a Human Endeavour links
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Science can be limited in its ability to provide definitive answers to public debate; there
may be insufficient reliable data available, or interpretation of the data may be open to
question (ACSBL107)
People can use scientific knowledge to inform the monitoring, assessment and evaluation
of risk (ACSBL106)
Snake antivenom production
Globally, hundreds of thousands of people die of snake bite each year, most of them in developing
countries. The venom of many species of snake contains neurotoxins that cause paralysis.
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Antivenom is conventionally manufactured by ‘milking’ venomous animals, immunising large
animals with small quantities of the collected venom and then extracting the antibodies produced
in the animals’ blood. The process is risky and labour-intensive and the products are highly
expensive, often provoke allergic reactions, and are difficult to transport and store, making
availability of antivenoms a significant challenge in developing countries. Some organisations have
called for global cooperation and investment by science, business and government bodies to
increase the availability of antivenoms in the developing world (ACSBL108). Part of this challenge
may be met by new research that has demonstrated it is possible to generate an antibody response
using synthetic DNA which is injected into cells to produce a protein that closely resembles the
most toxic parts of the actual venom (ACSBL109).
Science as a Human Endeavour links
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Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL109)
International collaboration is often required when investing in large-scale science projects
or addressing issues for the Asia-Pacific region (ACSBL108)
Infectious disease
Modeling disease outbreak and spread
The first mathematical models of the spread of disease were developed in the eighteenth century
by Daniel Bernoulli, who created a model to predict increased life expectancy if populations were
inoculated against smallpox. As these models preceded an understanding of germ theory, it was
not until the early twentieth century that more reliable models were developed (ACSBL104).
Contemporary models project how the disease will progress and simulate the effects of possible
interventions. Such models are used to inform public health interventions such as mass vaccination
programs. Supercomputing increased processing capacity and data storage has enabled models to
increase in their complexity, with new variables examined and new relationships found, such as the
relationships between epidemic frequency and location and factors such as population size,
environmental change and antibiotic resistance (ACSBL103).
Science as a Human Endeavour links
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ICT and other technologies have dramatically increased the size, accuracy and geographic
and temporal scope of data sets with which scientists work (ACSBL103)
Models and theories are contested and refined or replaced when new evidence challenges
them, or when a new model or theory has greater explanatory power (ACSBL104)
Managing pandemics in the Asia region
Epidemics and pandemics that are global or regional are becoming more prevalent, with outbreaks
of diseases such as HIV/AIDS, diphtheria, malaria, measles and swine flu at a global level, and
Severe Acute Respiratory Syndrome (SARS) and avian flu at regional levels. Asia has been described
as particularly susceptible to epidemics and pandemics of infectious disease due to increasing
migration and global travel, high population density in urban areas and underdeveloped healthcare
systems in some countries. The high cost of drugs and vaccines presents a particular challenge for
developing countries in Asia, as does community mistrust of vaccination (ACSBL105). International
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business has recognised the costs associated with global and regional epidemics and has advised
that businesses, governments and international organisations should collaborate to help prevent
infectious diseases among poor populations by strengthening regional and national pandemic
preparedness planning and expanding public-private partnerships to increase drug and vaccine
availability (ACSBL108).
Science as a Human Endeavour links
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The acceptance of scientific knowledge can be influenced by the social, economic, and
cultural context in which it is considered (ACSBL105)
International collaboration is often required when investing in large-scale science projects
or addressing issues for the Asia-Pacific region (ACSBL108)
Quarantine and biosecurity
As an island nation, Australia has had an advantage over many other countries because its borders
are easier to protect against the influx of disease-carrying materials and organisms. However, as
global trade and air travel become more prevalent, it is increasingly important for Australia to
protect its agriculture industry and environment through quarantine measures. These include
surveillance, monitoring, examination and clearance activities and conform to policies and
protocols that are based on scientific data and risk analysis (ACSBL109). Quarantine policy is
determined through bilateral and multinational negotiations and involves consideration of
protection of Australia’s animal and plant health status, Australia’s international obligations, the
trade impact of quarantine policies, and environmental protection (ACSBL108).
Science as a Human Endeavour links
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Scientific knowledge can be used to develop and evaluate projected economic, social and
environmental impacts and to design action for sustainability (ACSBL109)
International collaboration is often required when investing in large-scale science projects
or addressing issues for the Asia-Pacific region (ACSBL108)
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