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STAGE 2 BIOLOGY
ASSESSMENT TYPE 2: Skills and Applications Task
Extended Responses
Group A Topic 3
Protein molecules consist of subunits called amino acids. These form in a single chain held
together by peptide bonds forming an initial or primary structure. This structure becomes a
secondary structure when the first chain folds specifically into a new shape held by hydrogen
bonds, making a helical structure. The chain once again folds, joining with disulfide bonds
forming a 3-dimensional tertiary structure. All of these chains are formed into specific shapes
and orders due to the sequence that the 20 different amino acids make. The structures all
carry out different tasks.
When a protein like this is created, it has an overall three-dimensional shape which allows
another molecule with a complementary shape to join to it.
An example of this specific binding and recognition is enzymes and their substrates. The
active site of an enzyme is specific to one sort of molecule which attaches to the enzyme and
allows it to form a product or products. The presence of the enzyme causes the product form
much faster than it otherwise would. It is called catalysing a reaction in the body.
This enzyme can be inhibited by molecules with a similar shape to the substrate which attach
to the active site and prevent substrate molecules from joining to it.
Another example of the importance of shape is cell membrane receptors which lie on the
membrane of the cell and are specific to certain hormones. Once the complementary
hormone attaches to the receptor molecule, specific reactions are triggered inside the cell.
Group B Topic 6
Drugs could enter a cell passively by passing through a channel protein in the cell membrane.
The process called diffusion means that the drug could pass through the channel protein if
there is a high concentration of the drug in the environment outside the cell and a low
concentration of the drug inside the cell. The drug also has to be a molecule that is small
enough to pass through the channel protein.
Drugs could be actively transported into the cell by endocytosis. The cell membrane
invaginates around the molecule. The cell membrane then encloses the molecule into a
vesicle and it is incorporated into the cytoplasm of the cell. This is a way that large molecules
can enter a cell.
Drug testing programs have benefitted society. People can be randomly drug tested by police.
This would help catch drug addicts and it may also reduce the amount of drug use because
people do not want to be caught. It would make road safety better with fewer people driving
while affected by drugs.
Page 1 of 4
Stage 2 Biology annotated student work for use from 2011
148093487 (October 2010)
© SACE Board of South Australia 2010
Application and
Knowledge and
Understanding
The response
uses appropriate
subject-specific
language highly
effectively and
demonstrates a
deep
understanding of
biological
concepts
required in this
answer.
Drug testing programs have also stopped some people in sport from using performanceenhancing drugs. This means that sport competitions are fairer because the athletes are
competing fairly and if they win the competition it is because they have the best skills and not
because they are being helped by drugs that stimulate their reaction time or allow them to
have a higher concentration of oxygen in their blood stream.
The use of pesticides has benefitted society. Pesticides kill off pests that feed on crops so this
means that the yield increases and more food is available. This benefits society because
there are more people in the world so more and more food is needed.
Some pesticides also have disadvantages. Some pesticides, such as DDT, can accumulate in
the food chain. Higher order consumers end up with a concentration of the pesticide that is
high enough to cause damage. This can result in some species being killed off, affecting the
biodiversity in the area where the pesticide is being used.
Group C
Topic 9
Knowledge and
Understanding
Uses knowledge
of biology
perceptively and
logically to
understand and
explain social or
environmental
issues.
Analysis and
Evaluation
Critically and
logically
analyses
connections
between
concepts, and
issues in biology.
Cells need to regulate their internal composition. The correct pH and concentration of
substances, enzymes and products is needed for chemical reactions to occur efficiently.
Waste products also need to be removed so that they do not accumulate in the cell and act
like a poison.
Some substances must be at a higher or lower concentration inside the cell than outside the
cell. This may be achieved by either active or passive transport. If the movement is by active
transport, a substance is moved against the concentration gradient from a region of lower
concentration to a region of higher concentration. Transport proteins in the cell membrane
pump specific molecules across the membrane using energy that has been released by the
breakdown of ATP to ADP and phosphate. These proteins are very specific in what they will
move and cells may have different types of transport in the membrane. In the diagram shown,
hydrogen ions are being moved against the concentration gradient by a specific protein for
these ions embedded in the membrane.
Knowledge and
Understanding
Makes good use
of relevant
diagrams,
referred to in the
response to
support
understanding.
Uses a variety of
formats to
communicate
knowledge and
understanding of
biology
coherently and
effectively.
The energy in ATP comes from respiration. Glucose is broken down over many steps and
each step uses a different enzyme. Some of the first steps in respiration require ATP but the
later steps produce a lot more ATP. ADP is converted ATP by connecting the phosphate to an
ADP molecule using the energy from the glucose molecule. When cell processes require
energy, ATP is broken down to ADP and phosphate, releasing energy. The ADP and
phosphate can be reused by being converted back to ATP, using energy from respiration. This
is known as the ATP cycle, and is shown below:
Page 2 of 4
Stage 2 Biology annotated student work for use from 2011
148093487 (October 2010)
© SACE Board of South Australia 2010
Additional comments
Evidence from this assessment contributes to an overall assessment for the Investigations Folio in relation to:




analysis and evaluation of connections between data, concepts, and issues in biology (Analysis and
Evaluation)
appropriate use of biological terms, conventions, formulae, and equations (Application)
demonstration of knowledge and understanding of a range of concepts (Knowledge and Understanding)
use of a variety of formats to communicate knowledge and understanding of biology. (Knowledge and
Understanding)
Page 3 of 4
Stage 2 Biology annotated student work for use from 2011
148093487 (October 2010)
© SACE Board of South Australia 2010
Performance Standards for Stage 2 Biology
A
Investigation
Analysis and
Evaluation
Application
Knowledge and
Understanding
Designs logical, coherent, and detailed biological
investigations.
Critically and logically analyses
and evaluates connections
between data, concepts, and
issues in biology.
Applies biological concepts and
evidence from investigations to
suggest solutions to complex
problems in new and familiar
contexts.
Consistently demonstrates a
deep and broad knowledge
and understanding of a range
of biological concepts.
Critically and logically selects and consistently
and appropriately acknowledges information
about biology and issues in biology from a range
of sources.
Manipulates apparatus and technological tools
carefully and highly effectively to implement wellorganised safe and ethical investigation
procedures.
Obtains, records, and displays findings of
investigations using appropriate conventions and
formats accurately and highly effectively.
B
Designs well-considered and clear biological
investigations.
Logically selects and appropriately acknowledges
information about biology and issues in biology
from different sources.
Manipulates apparatus and technological tools
carefully and mostly effectively to implement
organised safe and ethical investigation
procedures.
Obtains, records, and displays findings of
investigations using appropriate conventions and
formats mostly accurately and effectively.
C
Designs considered and generally clear biological
investigations.
Selects with some focus, and mostly appropriately
acknowledges, information about biology and
issues in biology from different sources.
Manipulates apparatus and technological tools
generally carefully and effectively to implement
safe and ethical investigation procedures.
Obtains, records, and displays findings of
investigations using generally appropriate
conventions and formats with some errors but
generally accurately and effectively.
D
Prepares the outline of one or more biological
investigations.
Selects and may partly acknowledge one or more
sources of information about biology or an issue in
biology.
Uses apparatus and technological tools with
inconsistent care and effectiveness and attempts
to implement safe and ethical investigation
procedures.
Obtains, records, and displays findings of
investigations using conventions and formats
inconsistently, with occasional accuracy and
effectiveness.
E
Identifies a simple procedure for a biological
investigation.
Identifies a source of information about biology or
an issue in biology.
Attempts to use apparatus and technological tools
with limited effectiveness or attention to safe or
ethical investigation procedures.
Attempts to record and display some descriptive
information about an investigation, with limited
accuracy or effectiveness.
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Critically and logically evaluates
procedures and suggests a
range of appropriate
improvements.
Systematically and perceptively
analyses and evaluates data
and other evidence to formulate
conclusions and make logical
and highly relevant predictions.
Uses appropriate biological
terms, conventions, formulae,
and equations highly
effectively.
Uses knowledge of biology
perceptively and logically to
understand and explain social
or environmental issues.
Demonstrates initiative in
applying constructive and
focused individual and
collaborative work skills.
Uses a variety of formats to
communicate knowledge and
understanding of biology
coherently and highly
effectively.
Clearly and logically analyses
and evaluates connections
between data, concepts, and
issues in biology.
Applies biological concepts and
evidence from investigations to
suggest solutions to problems
in new and familiar contexts.
Demonstrates some depth
and breadth of knowledge
and understanding of a range
of biological concepts.
Logically evaluates procedures
and suggests some appropriate
improvements.
Uses appropriate biological
terms, conventions, formulae,
and equations effectively.
Uses mostly logical analysis
and evaluation of data and
other evidence to formulate
conclusions and make
consistent and relevant
predictions.
Applies mostly constructive and
focused individual and
collaborative work skills.
Uses knowledge of biology
logically to understand and
explain social or
environmental issues.
Analyses and evaluates
connections between data,
concepts, and issues in biology.
Applies biological concepts and
evidence from investigations to
suggest some solutions to
basic problems in new or
familiar contexts.
Evaluates some procedures in
biology and suggests some
improvements that are
generally appropriate.
Analyses and evaluates data
and other evidence to formulate
conclusions and make simple
and generally relevant
predictions.
Uses generally appropriate
biological terms, conventions,
formulae, and equations with
some general effectiveness.
Uses a variety of formats to
communicate knowledge and
understanding of biology
coherently and effectively.
Demonstrates knowledge and
understanding of a general
range of biological concepts.
Uses knowledge of biology
with some logic to understand
and explain one or more
social or environmental
issues.
Applies generally constructive
individual and collaborative
work skills.
Applies different formats to
communicate knowledge and
understanding of biology with
some general effectiveness.
Applies some evidence to
describe some basic problems
and identify one or more simple
solutions, in familiar contexts.
Demonstrates some basic
knowledge and partial
understanding of biological
concepts.
Attempts to use some biological
terms, conventions, formulae,
and equations that may be
appropriate.
Identifies and explains some
biological information that is
relevant to one or more social
or environmental issues.
Attempts individual work
inconsistently, and contributes
superficially to aspects of
collaborative work.
Communicates basic
information to others using
one or more formats.
Acknowledges that connections
exist between data, concepts,
and/or issues in biology.
Identifies a basic problem and
attempts to identify a solution in
a familiar context.
Demonstrates some limited
recognition and awareness of
biological concepts.
Acknowledges the need for
improvements in one or more
procedures.
Uses some biological terms or
formulae.
Shows an emerging
understanding that some
biological information is
relevant to social or
environmental issues.
Describes basic connections
between some data, concepts,
and issues in biology.
For some procedures, identifies
improvements that may be
made.
Attempts to extract meaning
from data and other
observations and to formulate a
conclusion or make a simple
prediction that may be relevant.
Attempts to organise some
limited data or observations.
Shows emerging skills in
individual and collaborative
work.
Attempts to communicate
information about biology.
Stage 2 Biology annotated student work for use from 2011
148093487 (October 2010)
© SACE Board of South Australia 2010