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Command terms used in IB Biology
All IB Biology questions are built around command terms, which let you know exactly what is
expected of you. They are grouped according to the objectives of IB Biology:
Objective
Command Term
Example
Tips/Tricks
Objective 1:
Demonstrate an
understanding of:
Define: Give the
precise meaning of a
word or phrase as
concisely as possible.
“Define osmosis.”
Create a vocab list to
study for define
questions
Draw: represent by
means of a LABELED,
accurate diagram or
graph.
“Draw and label a
diagram of the
ultrastructure of a liver
cell.”
A straight edge should
be used for straight
lines.
● scientific facts
and concepts
● scientific
methods and
techniques
● scientific
terminology
● methods of
presenting
scientific
information
Diagrams should be
drawn to scale.
Here’s a list of syllabus
statements that could ask
for drawings…
Graphs should have
points correctly
plotted.
Here’s a list of syllabus
statements that could ask
for graphs...
Label: Add labels to a
diagram.
“Label the sense and
antisense strands.”
List: give a sequence
of names or other brief
answers with no
elaboration, each one
clearly separated from
the others.
“List two causes of
variation within a gene
pool.”
Measure: find a value
for a quantity.
No past exams have
Bring a ruler to the
used this command
exam!
term! However,
accurate measurement
is often needed to
answer other
questions.
State: give a specific
name, value or other
brief answer
“State the source,
substrate, products
and optimal pH
condition for lipase in
the human digestive
system.”
No supporting
argument or
calculation is
necessary.
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​
Objective
Command Term
Example
Tips/Tricks
Objective 2: Apply and
sse:
Annotate: add brief
notes to a diagram.
“Annotate the electron
micrograph of the
Escherichia coli cell
with the function of
the structures labelled
I and II.”
Annotating is more
than labeling; include
causes or
explanations.
Calculate: find an
answer using
mathematical methods
“Calculate the change
in temperature in each
cup after 20 minutes.”
Show the work unless
instructed not to do so.
● Scientific facts
and concepts
● Scientific
methods and
techniques
● Scientific
terminology to
communicate
effectively
Be sure to include the
unit in your answer.
Describe: Give a
detailed account.
Describe the trends
shown by the graph for
dissolved oxygen in
water discharged from
the mouth.”
Distinguish: give the
differences between
two or more different
items.
“Distinguish between
the structures of the
different types of fatty
acids in food.”
Estimate: find an
approximate value for
an unknown quantity,
based on the
information provided
and scientific
knowledge.
“Estimate the
difference between
mean blood glucose
levels in control and
IKO older female
mice.”
Identify: find an answer
from a number of
possibilities.
“Identify the organelles
labelled I and II on the
electron micrograph.”
Outline: give a brief
account or summary.
“Outline why the
number of trophic
levels is limited in a
food chain.”
Include essential
information only.
Objective
Command Term
Example
Tips/Tricks
Objective 3: Construct,
analyse and evaluate:
Analyze: interpret data
to reach conclusions
using essential
elements or structures.
“Analyse the graph to
Use data provided in
obtain two conclusions the question to reach a
about the
conclusion.
concentration of
● Appropriate
methods of
presenting
scientific
information
● Hypotheses,
Estimate questions are
often based on graphs
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​
research
questions and
predictions
● Scientific
methods and
techniques
● Scientific
explanations
sodium– potassium
pumps.”
Comment: Give a
judgment based on a
given statement or
result of a calculation.
“Comment on whether
the experimental data
supports the observed
data from the ocean.”
Compare: give an
account of similarities
and differences
between two (or more)
items, referring to both
(all) of them
throughout.
“Compare the pattern
of GH3 transcription
with the pattern of
auxin concentration in
the stem base control
cuttings.”
Comparisons can be
given using a table.
Compare and
Contrast: Give an
account of similarities
AND differences
between two (or more)
items or situations,
referring to both (all) of
them throughout.
“Compare and contrast
the changes in auxin
concentration in the
stem base over time
for the control and
NPA-treated cuttings.”
A table can be used.
Construct: represent or “Construct a possible
develop in a
food chain using three
diagrammatic or
of the organisms
logical form.
shown opposite,
stating the trophic level
to which they belong.”
Deduce: reach a
conclusion from the
information given.
“Deduce from the data
in the bar charts which
factors were and were
not correlated
significantly with the
number of oysters
drilled by the
gastropods.”
Design: produce a plan, “Parts of a
object, simulation or
dichotomous key to
model.
organisms A, B, C and
D are shown. Design
missing parts of the
key using features
visible in the following
diagrams.”
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Determine: find the
only possible answer.
“Determine the
phenotype of Aabb.”
Discuss: give an
account including,
where possible, a
balanced range of
arguments,
assessments of the
relative importance of
various factors or
comparisons of
alternative hypotheses
supported by
appropriate evidence.
“Discuss the
advantages and
disadvantages of the
use of adult stem
cells.”
Evaluate: assess the
implications and
limitations.
“Using all the data,
evaluate how CO2
concentrations affect
the development of
oysters and their
predation by
gastropods.”
Explain: give a clear
account including
causes, reasons or
mechanisms.
“Explain how
hormones are used to
control the human
menstrual cycle.”
Predict: give an
expected result.
“Predict with a reason, Look for trends shown
whether the effects of in provided data and
UV on plants will
continue them onward.
increase or decrease
the greenhouse effect.”
Sketch: Represent by
means of a LABELED
diagram or graph.
Example:
“Sketch the hormone
changes between days
13 and 28 on the
graphs below for a
woman in her normal
menstrual cycle.”
Suggest: propose a
hypothesis or other
possible answer.
“Suggest reasons for
these trends in
dissolved oxygen.”
Sketch should give a
general idea of the
required shape or
relationship. Should
include relevant
features.
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Before using any of the files available on this site, please familiarize yourself with the Creative Commons Attribution
License. ​It prohibits the use of any material on this site for commercial purposes of any kind.