Life Science—Biology*
Concept and Skill Progressions
Sequenced concepts and skills to support student learning of science and
technology/engineering from PreK to high school, informed by preconception, conceptual change, and learning progression research
Massachusetts Department of Elementary and Secondary Education
November 15, 2010
* Please note there are corresponding documents available for:
Earth and Space Science
Physical Science—Chemistry/Introductory Physics
Technology/Engineering
The concept and skill progressions are meant to inform and support curriculum and instruction,
but are not meant to replace the current Science and Technology/Engineering (STE) standards.
Curricular and instructional goals should continue to be aligned with current STE standards;
the state’s STE MCAS tests will also continue to reference current STE standards.
November 15, 2010
Table of Contents
Section
Page
Introduction to the Concept and Skill Progressions
2
Visual organization of the Concept and Skill Progressions (Figure 1)
4
Life Science—Biology Concept and Skill Progressions**
Anatomy & Physiology
5
Cell Biology & Biochemistry
14
Genetics
24
Evolution & Biodiversity
32
Ecology
38
Contributors:
Barbara C. Buckley, WestEd, California
Dr. Ravit Duncan, Rutgers University, New Jersey
Dr. Erin Marie Furtak, University of Colorado, Boulder, Colorado
Dr. Rebecca Jordan, Rutgers University, New Jersey
Dr. Joel Michael, Rush Medical College, Illinois
David Mellor, Rutgers University, New Jersey
Dr. Harold Model, Bastyr University, Washington
Dr. Aaron Rogat, Teachers College, Columbia University, New York
Dr. Leona Schauble, Vanderbilt University, Tennessee
Dr. Ann Wright, Canisius College, New York
** There is not a concept and skill progression for every topic typically found in state Life
Science—Biology standards; authors were only available for the five topics included. **
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November 15, 2010
Introduction to the Concept and Skill Progressions
This document presents concept and skill progressions for 5 common Life Science—Biology
topics. These concept and skill progressions articulate idealized sequences of concepts and skills
that can effectively support student learning of core scientific ideas from PreK to high school.
These summaries draw from a variety of research genres, including pre-conception, conceptual
change, and learning progression research on science education. These summaries are written
and reviewed by educational researchers who study student learning of each science and
technology/engineering (STE) topic. They are set up to reflect a learning progression approach to
student understanding of core STE ideas. These are research-based resources that can inform
work in curriculum development, instruction, and assessment. These are also have been
referenced, in conjunction with the many other available STE resources, by the Massachusetts
STE Review Panel in the revision of Massachusetts STE student learning standards.
Learning progression research is beginning to provide a framework for understanding student
preconceptions, obstacles to learning, and transitional ideas about the world as they learn
science. A learning progression makes explicit the successively more complex ways of thinking
about STE concepts and skills that students develop over time (Smith, Wiser, Anderson, &
Krajcik, 2006). While learning progressions are research-based, they are hypothetical; they
propose how to bridge the intuitive ideas children have developed about core ideas before formal
instruction with the scientific version of that idea if students are exposed to appropriate curricula
(Corcoran et al, 2009). Additionally, ideas in learning progressions are not always scientifically
accurate. For example, the idea that any piece of matter, however small, has weight is not
completely scientifically accurate as it only applies to matter in a gravitational field. It belongs in
the learning progression, however, because it makes the idea that atoms are the key components
of matter easier to accept (students often believe that weight is not a property of matter, and if a
piece of material gets very small it has no weight). Considering student cognition from a learning
progression basis allows us to take students’ initial ideas into account, to characterize productive
transitional ideas, and to design curricula that move students' network of ideas toward scientific
understanding in a purposeful way.
The Massachusetts Department of Elementary and Secondary Education has asked educational
researchers to draw from the research literature on students’ pre-conceptions, conceptual change,
and, where available, learning progressions to provide up-to-date summaries of how to sequence
student thinking and learning of common STE topics. The research base to complete this task is
certainly not complete, so for the grade ranges, domains, and/or concepts for which learning
progression research is not available, each author used available pre-conception and conceptual
change research to provide informed estimates of what a progression of learning is likely to look
like. So while the authors have made informed recommendations about when certain concepts
and skills should be introduced, these do not limit what or when students can learn those
concepts and skills. These are idealized articulations of how we would want students to progress.
The concept and skill progressions do, however, help to convey how to move young children’s
initial conceptualizations to scientific theory over time.
Each concept and skill progression includes both a “narrative storyline” as well as a “concept
and skill details” section that are intended to convey a story of how students’ conceptual growth
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November 15, 2010
can develop over time. Both sections tell the same story, just at different levels of detail. Each
concept and skill progression is organized to reflect the nature of initial ideas in a topic (lower
anchor); the 'stepping stones' that can serve as intermediary targets between initial ideas and
scientific theory; and specify the scientific core ideas, concepts and skills in that domain students
should achieve as the result of their education (upper anchor). It is important to note that each
grade-span cell in the details section should be read in its entirety; the individual concepts and
skills should be viewed as a set rather than individually. See Figure 1 on page 4 for more details
on the organization of the summaries. Providing a common template across topics allows
curriculum developers, educators, and others to make sense of particular core ideas, concepts and
skills in relation to each other across grade levels and topics. It is important to be clear that the
individual elements in the concept and skill progressions are not standards; taken together they
describe what students can know and do over time as they come to learn core scientific ideas.
These concept and skill progressions can be used in conjunction with the 2001/2006 STE strand
maps (http://www.doe.mass.edu/omste/maps/default.html; modeled on the AAAS Atlases of
Science Literacy) to visualize student learning over time. Productively building upon
relationships between ideas that span multiple grade levels will require greater communication
and coordination than is currently typical. Teaching that honors progressions of learning will also
require educators to clearly understand where their students currently are relative to desired
outcomes. This can be accomplished with pre-assessment strategies—including strategies that
move beyond simple identification of misconceptions—as well as greater differentiation of
lessons to meet the needs of particular students. Being able to access a variety of instructional
and learning resources, such as through the National Science Digital Library (NSDL;
http://strandmaps.nsdl.org/), will help educators implement these strategies. Coordinated use of
strand maps will help educators approach teaching and learning from a perspective where ideas
are consistently related to each other over extended periods of time. Such an approach can
effectively account for student conceptions and more effectively promote achievement of science
and technology/engineering standards.
Please note: Topics included in this document were selected based on both available research
and the availability of an author to write the summary. In some cases research is available but an
author was not, or some common concepts within a topic were omitted due to lack of a research
base; these are not exhaustive summaries. These concept and skills progressions will likely be
updated in the future as additional research and information is available. Please direct any
comments, feedback, resources or research that may inform edits or additions to these concept
and skill progressions to mathscitech@doe.mass.edu.
References
Corcoran, T., Mosher, F., Rogat, A. (2009). Learning Progression in Science: An evidence-based
approach to reform. Philadelphia, PA: Consortium for Policy Research in Education.
Smith, C.L., Wiser, M., Anderson, C.W., Krajcik, J. (2006). Implications of research on
children’s learning for standards and assessment: A proposed learning progression for
matter and the atomic molecular theory. Focus Article. Measurement: Interdisciplinary
Research and Perspectives, 14, 1-98.
3
Possible misconceptions, placed in the grade span
before they are addressed, are highlighted gray.
Read concept and skill detail section from left to right, from initial
ideas (pre-instruction) to culminating scientific ideas (high school).
Page 1:
Narrative
storyline
provides an
overview of
how student
ideas develop
across grade
spans.
Page 2+:
Concept and
skill detail
section (pg 2 &
3 of this
example)
provide specific
concepts by
core idea (rows)
and grade-span
(columns).
Stepping
stones move
students from
initial ideas to
scientific
understanding
(read each
grade-span cell
in its entirety).
Key
vocabulary
is indicated
in the grade
span it is
introduced.
Endnotes on
final page(s)
include
comments on
particular
concepts,
including
instructional
strategies, limits
to student
understanding,
and additional
explanation.
Figure 1. Features of the concept and skill progressions, using Plate Tectonics as an example.
4
Human Anatomy & Physiology
November 15, 2010
Human Anatomy & Physiology
Concept and Skill Progression for Human Anatomy & Physiology
The progression if organized in five core ideas: That organisms carry out functions at different levels of organization simultaneously; that information flows within and between
the cells and between the environment and the organism; that homeostasis maintains an internal environment at a “steady state”; that the laws of physics that apply to inanimate
objects also apply to living systems and can explain physiological phenomena; and that living organisms depend upon matter and energy transfer and transformations. Embedded
within these core ideas, are six body systems that students come to understand: The cardiovascular system and the respiratory system (Levels of Organization); The nervous system
and the reproductive system (Information Flow); The gastrointestinal system and the musculoskeletal system (Matter and Energy Transfer and Transformations). The inclusion of
homeostasis and causal relationships in the document are significant because it places an emphasis on processes by which many physiological mechanisms are governed.
NARRATIVE STORYLINE
Initial Ideas
Before instruction students have direct contact with their bodies and have observed life, vertebrate, invertebrate, and plants around them. They realize there are certain factors,
environment, food, water, and lack of predation, etc. that are necessary to keep things alive. There are different stages of life, being born, getting older, and growing taller and heavier.
Students have a general sense about alive or dead.1
Conceptual Stepping Stones
Early elementary students know that living things need water, food, and air. Students know that exercise and proper diet is healthy. Students can describe why drugs, smoking, and
alcohol are unhealthy. Students understand, like other organisms, humans vary in size, shape, skin color, body hair, facial features, muscle strength, handedness, and more. Students
know females have babies and males do not. Students learn that germs, too small to see, can affect the human body causing fever and other symptoms of illness.
Later elementary students can explain that the human body is made of different organs and more importantly that the different organ systems work together (respiratory-circulation,
circulation-digestive). Students realize that different factors influence both physical and mental growth such as proper nutrition, exercise, and sleep. Students understand life cycles
(babies needs are different from grandparents needs). Students understand humans have the ability to engage in learning and use the knowledge. Students understand some
environmental effects on humans, such as air pollution, pollen in the spring, or lack of food resources and water.
Middle school students understand structural and functional relationships such as an increase in surface area of the lungs allows for increase gas exchange, or the larger the muscle the
more work it can do. Students learn that there are different types of cells and that cells makeup the body. They understand there is a network of cell organelles that provide unique
functions that allow the cell to function properly. Students can describe levels of organization of the human body; cells, tissues, organs, and organ systems. Students understand the
various types of tissue such as fat, muscle, bone, etc. Students know that disease is a breakdown of body systems and can be caused by many different things. Students can describe
heredity as a passing of DNA, found in the nucleus of gamete cells, from one generation to the next. Students develop an understanding of risks and benefits in health.
Culminating Scientific Ideas2
High school students learn that the human body is made of exceptionally organized arrangement of differentiated cells that derived from a single cell and the genes of an individual’s
somatic cells are all the same and are made up of DNA molecules providing instruction for cellular activities. Students understand genes are inherited from parents and know different
genes control differentiation of cells. Students will gain knowledge about how cells are able communicate with other cells and function optimally within a narrow range of temperature
and acidity. Students examine how organisms are able to obtain and use resources to grow, reproduce, and maintain stable internal conditions while living in a constantly changing
external environment. Students can explain that chemical reactions of metabolism are necessary for cellular functions. Students understand cells get energy from food to maintain internal
activity and that cells must get rid of waste. Students understand how energy is temporarily stored in phosphate bonds of ATP. Students understand normal body functioning and the
interaction of body systems to be able to predict what happens to the function when hereditary and environmental situations occur. Students understand how exercise improves
cardiovascular endurance and can use mathematics to determine the changes.
Massachusetts Department of Elementary and Secondary Education
Human Anatomy & Physiology
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Human Anatomy & Physiology
November 15, 2010
Lower Anchor
Reflective of student concepts
Human Anatomy & Physiology
Upper Anchor
Reflective of science concepts
Reconceptualization
CONCEPT & SKILL DETAILS
Initial Ideas
Conceptual “Stepping Stones”
Culminating Scientific Ideas
Before instruction, students often
believe and can:
Students who view the world in this way believe and can:
Students who fully understand this topic
believe and can:
Pre-instruction
Levels of organization
Students know their body has
certain functions they can
control. They know they need
food, water, and they have to
be able to breathe. They
cannot breathe under water but
fish can.
Possible misconception:
Children think animals act like
people but don’t think of
people as animals (AAAS,
1993).
Cardiovascular System:
Students know there is an
organ called a heart and it
pumps blood. They know a
cut will cause bleeding.
K-2
Levels of organization
Cardiovascular System:
Students can identify the
heart, blood and vessels.
Students understand
systems are made of
several different parts that
carry on different functions
to keep the body going.
Students can take
measurements such as
pulse and see the variations
and yet the similarities of
their pulse.
Possible misconception:
Students often think there
is no connection between
other systems and the
cardiovascular system.
(Wright, n.d.)
3-5
6-8
High school
Levels of organization
Cardiovascular System:
Children know that the heart
pumps blood and that blood
is “important.”
Levels of organization
Cardiovascular System:
Students understand that blood carries
oxygen to cells of the body and
removes carbon dioxide and waste so
cells can continue their activities.
Oxygen enters the blood as it passes
through the lungs.
Levels of organization
Living organisms carry out functions at
many different levels of organization
simultaneously (from atoms to the whole
organism) that exist on different physical
scales.
Circulatory system is
integrated with the other
systems of the body,
particularly the respiratory
system.
Cardiovascular endurance is
increased with exercise. A
person can exercise longer
and more efficiently with an
improved cardiovascular
system.
Students know there are
various blood cells with
different functions,
including white blood cells
that protect the body from
foreign organisms such as
bacteria or viruses
(Benchmarks of Science
Literacy p. 145).
Possible misconceptions:
Students do not understand
Massachusetts Department of Elementary and Secondary Education
Student can explain that the heart is
two pumps, one after the other. Each
pump is made up of two chambers
separated by a valve. The right heart
pumps blood through a valve and then
through arteries to the capillaries in the
lungs. Blood leaves the lungs in veins
and returns to the left heart. The left
heart pumps blood through a valve to
the arteries and on to the rest of the
body (the capillaries in all the tissues).
Blood returns to the right heart in
veins.
Processes occurring on one level can
often be explained by mechanisms
occurring at lower levels (reductionism).
Cardiovascular System:
Students understand that the
cardiovascular system: is a closed system
bringing blood flow into every tissue and
organ; functions to deliver all needed
nutrients (glucose, oxygen) to all cells;
and removes all waste products (carbon
dioxide and waste products of
metabolism) from cells.
Students understand that the
circulatory system includes various
vessels all of which contain blood, but
that they are of different sizes that
have different functions.
Possible misconceptions:
After leaving the heart, blood is
Human Anatomy & Physiology
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Human Anatomy & Physiology
November 15, 2010
Human Anatomy & Physiology
that cells must get rid of
waste to stay alive. (Wright,
n.d.)
carried to several organs (kidney,
liver) before returning to the heart.
(Wright, n.d.)
Blood characteristic changes
depending what it is
carrying. If it is carrying
oxygen it is “clean” if it is
carrying carbon dioxide and
waste it is considered dirty.
(Wright, n.d.)
Very small chunks of fat float in blood
to heart where they can clog the
vessels and cause heart attacks.
(Wright, n.d.)
Student may believe that the
cardiovascular system is an open
system. (Wright, n.d.)
Cells exist in isolation with no
connection to circulation. (Wright,
n.d.)
Respiratory system:
Students know they need air or
oxygen to live and understand
that breathing pertains to
simply inhalation and
exhalation (ventilation).
Possible misconception:
Students may believe that the
respiratory system LETS air in
and out so you can breathe.
(Wright, unpublished
research)
Respiratory system:
Students know that they
breathe using their nose or
mouth and that when they
breathe in, their rib cage
moves up and out. They
notice that when they
breathe out, their rib cage
moves back down and in.
Students know that they
need to breathe to stay
alive. Students know that it
is hard to hold their breath
for too long and breathing
rate increases with
exercise.
Respiratory system:
Students can explain that
when they breathe, air
containing oxygen moves
into the lungs. They know
they breathe out carbon
dioxide.
Possible misconceptions:
Students may think that
“air” gets to the tissues in
special “tubes.” (Wright,
n.d.)
They may also believe
breathing and respiration
mean the same thing.
(Wright, n.d.)
Students know of
(respiratory) diseases such
as asthma.
Massachusetts Department of Elementary and Secondary Education
Respiratory system:
Students understand that breathing is a
mechanical process: They understand
the structures and functions of the
trachea, lungs, bronchi, bronchioles,
ribs, rib-cage, and diaphragm and
understand when the diaphragm
contracts, air rushes in, and when the
diaphragm relaxes, air is pushed out.
Students are able to collect and
analyze breathing rate and heart rate
data and explain the relationship
between the two.
Possible misconceptions:
Air moves in and out of the esophagus
to the lungs. (Wright, n.d.)
Gas exchange is different at the level
of the lungs and the cells. Gas
exchange is different for oxygen and
carbon dioxide. (Wright, n.d.)
Respiratory system:
Students understand that breathing occurs
because of air pressure differences
between the lungs and the atmosphere
and they know that air moves from an
area of high pressure to low pressure.
Students understand that gases are
exchanged during breathing between the
air in the alveoli and the blood in the
capillaries entirely by diffusion.
Students understand that breathing is an
autonomic response and that maintaining
the oxygen to carbon dioxide ratio in the
blood is related to homeostasis.
Students understand that the respiratory
system: obtains oxygen from the
atmosphere; transports oxygen in the
blood bound to hemoglobin; disposes of
carbon dioxide to the atmosphere; moves
air into and out of the lungs by muscle
contraction.
Human Anatomy & Physiology
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Human Anatomy & Physiology
November 15, 2010
Human Anatomy & Physiology
Students understand oxygen and carbon
dioxide exchange and that carbon dioxide
is produced by cellular metabolism.
Information flow
Nervous system:
Students know that there are
senses (hearing-ears, visioneyes, taste-tongue, smell-nose,
touch-skin) which determines
behavior ( for example, if they
see a car on the road they do
not cross the street; if they are
cold they put on coat).
Information flow
Nervous system:
Students know that there
are, and can comprehend,
senses (hearing-ears,
vision-eyes, taste-tongue,
smell-nose, touch-skin; for
example, they know color,
odors, thorns, temperature
changes, and pain).
Information flow
Nervous system:
Students can explain that the
brain receives signals (from
their senses), acts on the
signals, and sends signals to
controls responses of various
parts of the body.
Information flow
Nervous system:
Students understand that their muscles
(skeletal system) are controlled by the
brain (nervous system).
Students realize the nervous system
allows learning to occur and therefore,
people’s ability to interact with their
environment.
Nervous system:
Students recognize that the nervous
system is made up of special cells called
neurons which generate electrical signals
that travel over long processes throughout
the body carrying information from the
external world and the internal
environment and information to muscles
and glands.
Children know that the
brain is important and that
we “think” with it.
Students understand that
the skull is bone and
protects the soft brain
tissue. They can also
explain why it is important
to protect the brain (such
as by wearing a bicycle
helmet) so they can
maintain their senses
(Wright and Bork,
Unpublished research,
2010).
Reproductive system:
Students know that a
woman cannot have a baby
without a man. Students
Information is passed from neuron to
neuron by chemical transmission at
synapses, some of which are excitatory
and some of which are inhibitory.
Information is also passed from cell to
cell via ion flow through the gap
junctions that connect them.
The body is made of
components that help
people to look, find and
ingest food when hungry
and know when there is
danger.
Reproductive system:
Students know that women
have babies and men do not.
Information flow
Life requires information flow within and
between cells and between the
environment and the organism.
Students understand that the nervous
system and endocrine system work
together.
Reproductive system:
Students are aware of
similarities in appearance
between parents and children.
Massachusetts Department of Elementary and Secondary Education
Reproductive system:
Students understand sexual
reproduction at the level of the
specialized gametes.
Reproductive system:
Students know that the reproductive
system in both males and females
produces sex hormones that regulate
Human Anatomy & Physiology
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Human Anatomy & Physiology
Students have a sense of
human development, baby,
toddler, and older persons.
Students are aware of
variation among people.
Homeostasis
Students know that water,
food, and air are necessary for
life.
Students understand the
difference between being sick
and well.
Students are aware of the
urinary system beginning with
potty training and if they drink
a lot of liquid they urinate
more often. They know they
have control urination to a
certain point.
can explain that men and
women have different parts
and that what differentiates
the genders.
November 15, 2010
Students recognize that traits
are related to (the result of)
DNA.
Students understand that
certain characteristics are
inherited (eye color)
whereas other
characteristics are learned
like language
Homeostasis
Students understand that
the body needs to maintain
a constant temperature to
keep it operating
appropriately and food and
water are necessary to
maintain health.
Students know that body
systems need to work
together to maintain life.
Human Anatomy & Physiology
Students are aware that there can be
mutations in genes that can cause
diseases.
reproductive behavior and produces the
gametes (sperm and ova) required for
actual reproduction to occur.
Students learn about sexually
transmitted diseases and how easily
they can be spread.
Students understand that meiosis allows
for genetic variation due to gene
recombination brought about by
independent assortment, crossing-over
and random fertilization.
Students recognize that reproduction is
essential for the survival of a species.
Homeostasis
Students understand that cells
make up the body and need
specific requirements to
operate effectively.
Homeostasis
Students know that energy balance is
important and that the lungs provide
oxygen to use in the combustion of
food.
Possible misconception:
Students believe the body
contains cells but not that the
body is made of cells.
(Wright, n.d.)
Students can discuss how the
circulatory system moves substances to
or from cells where they are required or
created; acting in response to changing
needs of the system as a whole.
Students know that the body
must get rid of waste
products through the urinary
system.
Students understand that human heart
rate and the components in blood stay
within normal ranges. These ranges
are used to determine whether people
are well.
Students may be familiar with
certain (endocrine) diseases
such as diabetes.
Students know that kidneys make
urine from blood and that urine is a
waste product.
Students know the basic structures of
the urinary system and the function of
the structures (kidneys filter blood to
separate molecules; ureters are muscular
tubes that takes the urine to the urinary
bladder; the bladder stores the urine;
and the urethra takes the urine out of the
Massachusetts Department of Elementary and Secondary Education
Homeostasis
Students understand the principal of
homeostasis: humans normally maintain a
“steady state” internal environment that is
different than the external environment
and that the stability of the internal
environment occurs via information flow
in the form of negative feedback which is
integrated by the nervous and endocrine
systems.
Students understand that the activity
(behavior) of all of the systems is to
maintain a state of constancy in the body.
Possible misconception:
Many student think that homeostasis
means “normal,” and, while the
homeostatic mechanism tends to return a
system back toward normal. The new
steady state may still represent abnormal
function.
Students understand that kidneys
eliminate waste products and contribute
to the maintenance of a constant chemical
environment in the body and water
balance (blood pressure).
Human Anatomy & Physiology
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November 15, 2010
Human Anatomy & Physiology
body).
Students are able to compare and
contrast the different functions of the
urinary system and the digestive
system in removing waste from the
body.
Students know that hormones are
released from glands for regulating
growth, development and reproduction.
Students know that the body is made up
of a variety of types of cells.
Students understand that the endocrine
system produces chemical signals
(hormones) that regulate:
* Metabolism (storage and use of
energy);
* Water and electrolyte balance;
* Reproduction; and
* Growth (bone and soft tissues) and
development.
Hormones accomplish this by altering the
metabolism (the biochemistry) of cells.
Students know that specific systems are
made of specific types of cells and the
systems are coordinated together to
maintain balance.
Causal mechanisms
Children realize when
exercising, breathing
increases, sweating starts,
maybe feel heart rate increase
and can cause the desire for
water (thirst).
Causal mechanisms
Students can describe basic
cause and effect
relationships (for example,
if they feel hungry and eat
then they feel better, if the
hit their body accidently
with a hammer a bruise
occurs).
Causal mechanisms
Students understand that
healthy habits will help the
body whereas unhealthy
habits can harm the body.
Matter/energy transfer and
transformations
Students know they need
energy to be active4 or know it
is important to eat for energy,
growth and development.
Matter/energy transfer and
transformations
Students know food is
changed into energy.
Matter/energy transfer and
transformations
Students understand that
everything that happens in
the body requires the
expenditure of energy that is
derived from the food we
eat.
Students know cells need
nutrients for cellular work
and making structures.
Additionally, food is
changed into various
Massachusetts Department of Elementary and Secondary Education
Causal mechanisms
Possible misconception:
Students have difficulty distinguishing
between cause and effect within body
systems (does a pressure change cause
a change in lung volume, or visa
versa?). (Michael, 2007)
Causal mechanisms
The laws of physics and chemistry
describe the functioning of the organism,
and there are knowable physical causes
for physiological phenomena.
Matter/energy transfer and
transformations
Students can explain that metabolism
(chemical reactions) is necessary to
provide cells energy to carry out
cellular function. Necessary molecules
for the organism to survive come from
the metabolism of food which also
provides energy that can be used for
heat.
Matter/energy transfer and
transformations
Living organisms must obtain matter and
energy from the external world. This
matter and energy must be transformed
and transferred in varied ways to build the
organism and to perform work.
Students can explain the mechanisms
producing a response or predicting the
occurrence of responses.3
ATP a small high-energy compound that
stores energy temporarily in a phosphate
bond.
Food molecules contain energy in their
bonds and when the bonds are broken
energy is released.
Human Anatomy & Physiology
10
Human Anatomy & Physiology
November 15, 2010
molecules to be used for
energy.
Gastrointestinal system:
Students understand food is
important for the body.
Possible misconception:
Students often believe the
body uses food in its original
form.
Gastrointestinal system:
Children know that food
goes into the stomach.
They know that “poop”
comes out the other end.
Gastrointestinal system:
Food is changed into
various molecules to be
used by organisms.
Various organs and tissues
function to serve the needs
of cells for food
Human Anatomy & Physiology
Possible misconceptions:
Metabolism is how fast energy is
produced. Food is not involved in
metabolic processes. Nutrients and
food is the same thing. Nutrients are
all the same type of molecule. Energy
and metabolism is the same. Energy is
only used for movement. Energy and
metabolism always increase at the
same time. (Wright, n.d.)
Gastrointestinal system:
Cells require nutrients, which are used
to provide energy for cellular work.
Also, nutrients provide the materials
that a cell or an organism need to build
cellular structures.
Inside the cell, functions occur such as
extracting energy from food and
getting rid of waste.
Energy changes from one form to
another in living things. Energy is
from oxidizing food, releasing some
energy as heat
Gastrointestinal system:
Students understand that the
gastrointestinal system breaks down large
molecules that make up food into smaller
constituent molecules and absorbs the
products of this breakdown and other
nutrients (like vitamins) into the body.
Students recognize that a major function
of the GI system is the absorption of
water. The greatest amount of absorption
occurs across the small intestine.
Possible misconception:
Many students believe that the
stomach is the organ of the digestive
system where most products are
transported to the rest of the body.
(Wright, n.d.)
Musculoskeletal system:
Children know bones are hard
and muscle is soft.
They also know muscles are
attached to bones and help us
Musculoskeletal system:
Children know that bones
are “strong,” that they can
break, and they can “heal.”
They know that muscles
are used to move.
Musculoskeletal system:
Possible misconception:
Students typically believe
that bones are inert; that
they are not living tissue.
(Wright, n.d.)
Massachusetts Department of Elementary and Secondary Education
Musculoskeletal system:
Students can explain the physics of the
interaction of bones and muscle which
act like a lever system for movement.
Calcium ions are released from bones
Musculoskeletal system:
Students know that muscles convert
biological energy in the form of ATP into
mechanical work (generating force or
shortening). For example, contraction of
skeletal muscles (those that are attached
Human Anatomy & Physiology
11
Human Anatomy & Physiology
November 15, 2010
move.
Human Anatomy & Physiology
into the bloodstream. Calcium plays an
important role in the physiology and
biochemistry of organisms.
Maintenance of a relatively constant
extracellular calcium ion
concentration is critical to the normal
functioning of many physiological
mechanisms such as contraction of
cardiac and smooth muscles,
fertilization, and neurotransmission.5
to bones) is triggered by neurons and
results in movement; contraction of
cardiac muscle causes the heart to pump
blood; and contraction of smooth muscle
causes the movement of food in the GI
tract and controls the flow of blood
through metabolizing tissues.
6-8
High school
Bone is a living tissue that has all the
requirements of other tissues in the body.
Grades
Pre-instruction
K-2
3-5
Heart, blood, vessels,
pulse, breathe, alive,
exercise, asthma, senses
(hearing, vision, taste,
smell, touch), food, brain,
skull, bone, tissue, baby,
gender, inherited,
characteristic, temperature,
health, body system, cause
and effect, energy,
stomach, muscle,
movement
Circulatory system,
respiratory system,
endurance, cell, white blood
cell, bacteria, virus, lung,
oxygen, signal, control,
trait, DNA, nutrient, cellular
structure, molecule,
organism, organ
Key Vocabulary
Carbon dioxide, waste, chamber,
valve, arteries, capillaries, veins,
capillaries, skeletal system, nervous
system, learning, environment, sexual
reproduction, gamete, mutation, gene,
disease, sexually transmitted disease,
combustion, heart rate, kidney, urine,
urinary system, dissolve, digestive
tract, hormone, gland, regulate,
growth, development, metabolism,
chemical reaction, heat, bond, oxidize,
lever, contraction, nerve conduction
Atom, mechanism, closed system,
glucose, atmosphere, hemoglobin,
neuron, chemical transmission, synapse,
excitatory, inhibitory, ion flow, gap
junction, endocrine system, gene
combination, sorting, recombination,
species, homeostasis, steady state,
negative feedback, blood pressure,
electrolyte, matter, transformation of
matter, transformation of energy, ATP,
phosphate bond, absorption, vitamin,
small intestine
Notes
(1) Within the following conceptual stepping stones, the following National Science Standards (NAP, 1996) must be integrated into lessons at the various grade levels: 1. Science
as inquiry; 2. Unifying concepts and processes in science, such as structure and function relationship in chemistry, life science, and physics or the concept as randomness; and
3. Science in personal and social perspectives. Science in personal and social perspectives can include health and wellness issues tied into anatomy and physiology.
(2) It is also important to provide a science in personal and social perspective to this topic (link to Health and Wellness Framework). Children assign illness to germs but they don’t
know the difference between contagious and non-contagious diseases. Washing hands can wash away germs (personal hygiene). Children understand that some foods are
healthy and some foods are not and if you eat too much you gain fat which is not healthy. Use of alcohol, tobacco, and drugs are unhealthy behavior. Students should
understand basic hygiene and safety measures. They also should learn that certain behaviors such as eating healthy foods and exercise are important to growth and development
and other behaviors are not healthy and can inhibit growth and development. These ideas can be integrated with the other human biology core ideas. Students should learn how
to stay healthy and well and also they should be able to inform their community about how to be healthy.
(3) It is essential that students recognize that understanding physiological systems requires the ability to think causally (in terms of chains of cause-and-effect relationships).
Mathematic models can be used (for example, cardiac output depends on Stroke Volume and Heart Rate: CO=SV x HR).
(4) Usually a phrase used by parents.
(5) Contraction of skeletal muscles does not depend on extracellular calcium ion concentration.
Massachusetts Department of Elementary and Secondary Education
Human Anatomy & Physiology
12
Human Anatomy & Physiology
November 15, 2010
Human Anatomy & Physiology
Authors and Reviewers
Dr. Joel Michael, Rush Medical College, Illinois (contributor)
Dr. Ann Wright, Canisius College, New York (contributor)
Dr. Harold Model, Bastyr University, Washington (reviewer)
References
American Association for the Advancement of Science. (1993). Benchmarks for Science Literacy. New York, NY: Oxford University Press.
Arnaudin, M. W. and Mintzes, J. J. (Feb, 1986). The cardiovascular system: Children’s conceptions and misconceptions. Science and Children, 58-51.
Biology Misconceptions (Revised July 1998). At http://tortoise.oise.utoronto.ca/~science/biomisc.htm.
Duit, Reinders has maintained a website for many years that contains the most comprehensive bibliography of student misconceptions in science (all disciplines). It can be found
at www.ipn.uni-kiel.de/aktuell/stcse.html.
National Research Council. (1996). National Science Education Standards. Washington, DC: National Academy Press.
Michael, J. (2007). What makes physiology hard for students to learn? Results of a faculty survey. Advances in Physiology Education, 31:34-40.
Michael, J., Modell, H., McFarland, J, and Cliff, W. (2009). The “core principles” of physiology what should students understand? Advances in Physiology Education, 33:10-16.
Mintzes, J. J., Trowbridge, J. E., Arnaudin, M., and Wandersee, J. H. (1991). Children’s biology: Studies on conceptual development in the life sciences. In Glynn, Yeany, and
Britton (eds)., The psychology of learning science (pp. 179-202). Hillsdale, NJ: Erlbaum.
Wright, A. n.d., Unpublished research.
Wright, A., and Bork. (2010) Unpublished research.
Massachusetts Department of Elementary and Secondary Education
Human Anatomy & Physiology
13
Cell Biology and Biochemistry
November 15, 2010
Cell Biology and Biochemistry
Concept & Skill Progression for Cell Biology & Biochemistry
The progression is organized in four core ideas: that cellular Structures are made of biologically important molecules: DNA, protein, carbohydrates, and lipids; that proteins play a
central role in the structure and function of cells; that the cell is the fundamental structural and functional unit of living things; that there are a variety of sub-cellular parts that have
specific structures and do specific functions for the cell. There are two significant implications of this progression: first, to truly understand and develop cell theory and
biochemical understandings of living organisms, students must develop a decent atomic molecular theory prior to covering these biology topics in high school; and second, that the
role of proteins have to be emphasized and elaborated, which means introducing some basic concepts about protein structure and function in middle school.
NARRATIVE STORYLINE
Initial Ideas
Before instruction students are likely to know about protein, fat, and sugar as food. They know that all life requires food and has a role in providing energy, but they don’t know the role
it plays in cellular building materials. Students often have difficulty distinguishing the difference between cells, molecules and atoms and recognizing that living organisms or cells are
made of molecules. Students have some understanding that something inherent in living things makes them different from non-living things and can identify many living things from
non-living things. They may not recognize that bacteria are cells or that they have DNA. Students likely believe plants are living, however they may anthropomorphize plants. A
particularly strong misconception is that plants take in food (from the soil) as opposed to generating their own food through photosynthesis. Most students know that parents produce
babies and that reproduction appears to be common to all animals but may not apply reproduction to all organisms.
Conceptual Stepping Stones
Middle school students recognize that living cells and the subcomponents are comprised of molecules. Students realize proteins are molecules that have specific shapes and identify the
importance of proteins in carrying out the work of cells. Students describe DNA as a long chain molecule packed inside of cells that have a role in influencing traits. Students can explain
that individual cells carry out all the basic functions of any living thing. They will have difficulty, however, moving between different levels of biological organization (e.g., cell to tissue
to organ to system). Students often confuse the relationship between a cell, a nucleus and biological molecule like proteins and DNA. Students realize that includes only proteins,
carbohydrates, and fats and can explain that food is used as both a source of energy and building materials in organisms. They realize that plants produce their own food and animals
must take it in by eating other organisms. Students can describe the mitochondrion as a cell structure where energy is released and transformed into chemical energy that the cell can use
later. They understand that plants undertake photosynthesis to produce food (glucose), but sometimes confuse the process of photosynthesis and respiration, particularly in plants.
Students can explain that all organisms need to reproduce (replicate), including single-celled organisms like bacteria.
Culminating Scientific Ideas
High school students describe the basic molecular structures and primary functions of the four major categories of organic molecules (carbohydrates, lipids, proteins, nucleic acids). They
can describe lipids as being long carbon-hydrogen chains that allow control of the flow of substances into and out of the cell. They can explain the central role that proteins play in
carrying out many of the basic functions that cells must undergo to survive and provide examples of some basic types of proteins and their basic functions. Students realize proteins are
built inside of cells and perform critical functions inside of cells. They recognize that proteins can act as an enzyme and that the structure of an enzyme is critical to its function. Students
can explain that in all organisms, genes in DNA provide instructions for the assembly of proteins and influence what proteins are present and how they function. They can draw subcellular organelles found inside a plant and animal cell, and relate those organelles to their functions. Students can predict what would happen if one of these structures was removed or
ablated. They can compare and contrast, at the cellular level, the general structures and degrees of complexity of prokaryotes and eukaryotes and predict what structures one would find if
looked at under the microscope. Students can compare and contrast a virus and a cell. They can identify the reactants, products, and basic purposes of photosynthesis and cellular
respiration and explain the interrelated nature of these in the cells of photosynthetic organisms. They can describe how ATP is generated when food substances are broken down and is
used by proteins to perform work inside of cells. Students can describe the cell cycle and the process of mitosis and explain the role of mitosis in the formation of new cells. Students can
describe how the process of meiosis occurs and is able to explain the importance of this process in sexual reproduction. They can compare and contrast mitosis and meiosis in terms of
the number of chromosomes (at the beginning and ending) and the types of cells in which these processes occur.
Massachusetts Department of Elementary and Secondary Education
Cell Biology and Biochemistry
14
Cell Biology and Biochemistry
Lower Anchor
November 15, 2010
Cell Biology and Biochemistry
Upper Anchor
Reconceptualization
Reflective of student concepts
Reflective of science concepts
CONCEPT AND SKILL DETAILS
Initial Ideas
Conceptual Stepping Stones
Culminating Scientific Ideas
Before instruction, students often believe
and can:
Students who view the world in this way believe and can:
Students who fully understand this topic believe and can:
Before Instruction
Middle School
Structures and function of important
biological molecules
Students will likely have heard of terms
like protein, fat, and sugar as part of
their diet.1 Students are also more likely
to think about the role of these
substances as food – as simply anything
useful that that is ingested (AAAS,
1993).
Possible misconceptions:
Students typically have difficulty
distinguishing the difference between
cells, molecules and atoms. They often
confuse the different entities and have
difficulty representing or identifying
where they are located. (CPRE, 2009).
Some students are unlikely to recognize
that living organism or cells are made
of molecules.
[Naive and early ideas about DNA or
genes are described in genetics]
Structures and functions of important biological molecules
High School
2
Relate and distinguish the size and relationship between cells, molecules, and
atoms. Recognize that living cells and all of the subcomponents are comprised
of molecules. [Link to matter in chemistry]
Recognize that carbon is a common element among all biological molecules
found in cells.
Recognize that there are simple or small molecules, like water and glucose inside
of cells, and much larger and complex molecules like proteins and DNA.
[Link to location of genes in genetics]
Proteins: Describe proteins as little machines that carry out the work of cells and
realize proteins are molecules that have specific shapes (e.g., like a tiny glove
that catches a ball, or a tiny channel through which only certain shaped objects
fit). Describe proteins as a long chains folded on itself to form a particular
shape.3
DNA (one of the 2 nucleic acids): Describe DNA as a long chain molecule4
packed inside of cells that have a role in influencing traits. Realize DNA/genes
provide information to build proteins.5
[Link to gene function in genetics]
Carbohydrates: Identify carbon as a key element in carbohydrates and explain
that carbohydrates are a food substance because they provide a source of energy
and building material for the cell. Recognize that smaller sugar molecules can be
linked together to form long chains of sugars and locate places in cells where
such sugars can be found.
Massachusetts Department of Elementary and Secondary Education
Structures and functions of important biological
molecules7
Students should know that cellular structures are
made of biologically important molecules: nucleic
acids (DNA, RNA), proteins, carbohydrates, and
lipids.
1. Each of these has a characteristic structure
through which it interacts with other
molecules; its functioning emerges from
these interactions.
2. Each is composed primarily of atoms of
carbon, nitrogen, oxygen, hydrogen,
phosphorous, and sulphur; but they require
interactions with minerals such as iron and
calcium to accomplish their functions.
3. Each molecule can be assembled and
disassembled through biochemical reactions.
Explain that biological organisms are comprised
primarily of very few elements, with the six most
common being C, H, N, O, P, and S. Explain that
carbon is an especially important element and serves
as a major atomic building block in important
biological molecules such as nucleic acids (DNA and
RNA), proteins (e.g. enzymes), carbohydrates
(sugars), and lipids (fats).
Describe the basic molecular structures and primary
functions of the four major categories of organic
molecules (carbohydrates, lipids, proteins, nucleic
acids).8
Cell Biology and Biochemistry
15
Cell Biology and Biochemistry
November 15, 2010
Lipids or fats: Recognize that fats can be burned (i.e. broken down) to release
energy and that lipids can be found in cell membranes. Therefore they can be
considered a source of energy and building material for the cell and satisfy their
scientific classification as food for living organisms. Identify long strings of
carbon atoms as a distinguishing characteristic of this type of molecule .6
Recognize that DNA, proteins, and some sugars are long “chains” that can be
broken down into their small subunits (or “chain links”). Conversely recognize
that these molecules can be reassembled from smaller subunits or molecules.
[Link to digestion and metabolism in anatomy and physiology]
Possible misconception:
Scale and size issues of cells and molecules continue to pose problems here.
Students are most likely to associate proteins with nutrition and not as a
molecule inside of cells that carry out work. (Duncan, n.d.). Given that students
often do not see the break down and reassembly of organic molecules in food
chains (AAAS, 1993) it is likely they likely are not going to see this occurring in
organisms either.
Cell Biology and Biochemistry
Describe proteins as being comprised of smaller
carbon-based subunits, amino acids, that are chained
together, and nucleic acids (DNA and RNA) as being
comprised of smaller units that are carbon-based
nucleotides. Finally, describe lipids as being
comprised of long chain of carbon atoms.
Explain that biological molecules have properties
and structures that are key to their function in cells.
In particular, describe proteins as essentially chains
that fold into a multitude of shapes to carry out an
infinite variety of functions inside of cells. Realize
that amino acids linked together have particular
properties that influence how the amino acids
interact with one another influencing how the
proteins fold (e.g. hydrophobic, hydrophilic,
positively charged, negatively charged, form bends
or bridges).9
DNA or RNA. Realize the nucleotide sequence
determines the sequence of amino acids in proteins.
[Link to genetics]
Lipids. Describe lipids as being long carbonhydrogen chains are hydrophobic, which means they
repel water and tend to stick together. This allows
the cell to control the flow of substances into and out
of the cell, in particular, water and substances
dissolved in water.
Centrality of protein function
Possible misconception:
Student likely to think about proteins
merely as a dietary need. (Duncan, n.d.)
Students are likely to have heard of the
term protein, but in the context of food
they take in or specific foods that are
high in protein like meat, milk, or
beans.10
Centrality of protein function11
Recognize that proteins carry out work insides of cells.
Describe or predict a few types of basic cell functions that are mediated by
proteins12 including transport of molecules into or out of cells through channel
proteins (e.g. the transport of glucose into cells), enzymes that break down or
assemble other cellular molecules during growth (e.g. the break down of glucose
inside of cells), and breaking down simple sugars inside of cells during cellular
respiration. Explain that such activities are mediated by proteins. 13 Recognize
that proteins are found in both plant and animal cells.
Massachusetts Department of Elementary and Secondary Education
Centrality of protein function15
Students know that proteins play a central role in the
structure and function of cells.
Explain the central role that proteins play in carrying
out many of the basic functions that cells must
undergo to survive16 (replication—requiring
biosynthesis of cellular molecules for growth and
repair; breaking down food—to extract energy and
building material; getting rid of waste; responding to
the environment and communicating with other
Cell Biology and Biochemistry
16
Cell Biology and Biochemistry
November 15, 2010
Possible misconception:
There is the possibility that if students focus on proteins as carrying out work
inside of cells (like little machines) and also maintain their strong association
with protein as a dietary substance, they may think proteins are taken in and used
by cells “as is.”14
Cell Biology and Biochemistry
cells) and provide examples of some basic types of
proteins (e.g. enzymes that facilitate chemical
reactions, membrane bound channel proteins that
allow molecules to flow through membranes, ligands
that bind to membrane-bound receptors and facilitate
inter-cellular communication, and cytoskeletal
proteins that provide structure) and describe their
basic activities or functions.17
Students realize proteins taken in through diet are
broken down into smaller units during digestion and
reassembled into proteins during cellular
metabolism.
Students realize proteins are built inside of cells and
perform critical functions inside of cells. Students
realize proteins are found in all cell types in all
organisms.
Recognize one major function of proteins is to act as
an enzyme. Explain that enzymes enable chemical
reactions to occur that normally would take much,
much longer to occur without assistance. Explain the
structure of an enzyme is critical to its function and
that if the structure is changed, due to changes in the
environment like pH, it can not perform its function.18
Cells as a central structural and
functional unit
Early on many students focus on
movement as a basic characteristic of
all life (Driver, 1994). Later they may
include notions related to requirements
for food and its role in providing
energy (but not necessarily cellular
building materials) (CPRE, 2008).
However, cells typically do not become
part of students’ conceptions of
essential attributes of life early on
(Driver, 1994)
Students likely believe plants are
living.
Cells as a central structural and functional unit
Explain that individual cells carry out all the basic functions of any living thing.
Explain that all organisms are composed of cells, and that many organisms are
single-celled (unicellular, e.g., bacteria). Relate through models or drawings
subatomic structures such as DNA or proteins, cells, tissues, organs, and systems
in plants and animals.19
Possible misconceptions:
Students may not believe that plants or fungi are composed of cells. Even if they
believe animals or plants are made of cells they will have difficulty identifying
what is composed of cells and what is not in an organism. They will not be able
to move between different levels of biological organization easily – e.g. cell to
tissue to organ to system to whole organism (CPRE, 2008). Early on children
may see cells as inanimate objects (NRC, 2007).
Massachusetts Department of Elementary and Secondary Education
Cells as a central structural and functional unit
Students know that the cell is the fundamental
structural and functional unit of living things, which
either as a single cell or as a system of cells,
accomplish functions such as
1. maintain an internal environment
2. growth and repair, and
3. reproduction.
Describe that all organisms are composed of cells.26
Explain that in all individual cells proteins facilitate
all the basic functions that living cells need to carry
out, even if they are a cell that constitutes a singlecelled organism like a bacterium. Also explain that
Cell Biology and Biochemistry
17
Cell Biology and Biochemistry
Possible misconceptions:
However, children may over-generalize
or anthropomorphize plants to think
that plants eat, sleep, etc. like humans.
(NRC, 2007)
Student often do not appreciate that
food is a source for BOTH energy and
building material. Water, vitamins, and
minerals are often mistaken as food –
simply because anything ingested is
considered food. (AAAS, 1993). A
particularly strong misconception is
that plants take in food (from the soil)
as opposed to generating their own
food through photosynthesis (NRC,
2007).
November 15, 2010
[This has relevance to anatomy and physiology as well]
Realize that all living things need food – including plants – and that food
includes only proteins, carbohydrates, and fats. Explain that food (glucose being
one type) is used as both a source of energy and as building materials in
organisms.20
Realize that plants produce their own food (glucose/simple sugar) and animals
must take it in by eating other organisms (like a plant or another animal).
[Link to ecosystems]
Explain that both animal and plant cells must extract energy from food – and that
both animal and plant cells break down glucose into smaller molecules and that
energy is released during this process. Students should describe the
mitochondrion as a cell structure where energy is released and transformed into
chemical energy that the cell can use later.21 In this process carbon dioxide and
water is released.
[Link to digestive and circulatory systems 22]
Identify mitochondria in both plant and animal cells, and chloroplasts in plants
cells. Explain why chloroplasts are in plant cells and not animal cells.
Photosynthesis & respiration: 23 Understand that plants take in water and carbon
dioxide from their environment and capture sunlight and use it as energy to
produce food (glucose) and oxygen. The glucose is stored in the plant while the
oxygen is released.
Recognize that photosynthesis and cellular respiration are chemical reactions
where principles of conservation of matter apply.
Track and identify energy types and transformations during processes that
involve chemical reactions such as photosynthesis and respiration.24
[Link to chemistry and physics strands]
Massachusetts Department of Elementary and Secondary Education
Cell Biology and Biochemistry
in all organisms’ genes in DNA provide instructions
for the assembly of proteins and influence what
proteins are present and how they function.
[Link to proteins in cells and genetics]
Realize (or predict) that for all the basic functions of
life that all cells must carry out, one can find similar,
or even the same proteins inside of the cell.27
Predict (or draw) what you would find if looked at
different tissue samples from plants and animals
under the microscope (e.g. tissue from intestine,
stomach, lung, brain, muscle, skin, or tissue from
leaf, root, or stalk).28
In multi-cellular organisms like plants and animals,
be able to compare and contrast two different cell
types (e.g. brain cell vs. muscle cell in animals or
leaf cell vs. root cell in plants).
Draw models of what sub-cellular structures one
could find inside of the following types of
organisms: a plant cell, an animal cell, a bacterium, a
fungi cell, and a protist. Predict if one would find
proteins for cellular respiration, assembly of DNA
molecules, assembly of protein molecules, and
photosynthesis (generated glucose using light
energy) in a plant cell or an animal cell. Identify
where these proteins might be located.
Photosynthesis & respiration: Identify the reactants,
products, and basic purposes of photosynthesis and
cellular respiration.29 Explain the interrelated nature
of photosynthesis and cellular respiration in the cells
of photosynthetic organisms. Identify where cellular
respiration and photosynthesis occur at the subcellular level.
Explain the important role that ATP serves in
metabolism.30 Describe how ATP is generated when
food substances are broken down (e.g. during
cellular respiration) and is used by proteins to
Cell Biology and Biochemistry
18
Cell Biology and Biochemistry
Cellular reproduction: Most students
know that parents produce babies and
that reproduction appears to be
common to all animals – but may not
apply reproduction to all organisms.
November 15, 2010
Possible misconceptions:
Students confuse the process of photosynthesis and respiration. They often do
not appreciate that plants also carry out respiration. Students sometimes conflate
breathing (exchange of gases carried out by lungs) with cellular respiration
(Anderson, n.d.; CPRE , 2008; Driver et al. 1984). Some students may overgeneralize functions of cells (NRC, 2007).
perform work inside of cells (e.g. when protein
enzymes build cellular molecules like DNA during
cellular reproduction).31
Cellular reproduction: Explain that all organisms need to reproduce (replicate),
including single-celled organisms like bacteria. Explain that animals and plants,
which are multi-cellular, reproduce by producing specialized cells (e.g. sperm
and egg in animals) and these sperm and egg must fuse together to produce a
new organism. After fusion, growth occurs as a result of multiple cell divisions,
generating more and more cells.
Cellular reproduction: Describe the cell cycle and
the process of mitosis.32 Explain the role of mitosis
in the formation of new cells, and its importance in
maintaining chromosome number during asexual
reproduction.
Recognize that some organisms have two sexes and that when they reproduce the
offspring are not identical to the parents, but instead there is variation among the
offspring and the offspring are a mix of both parents. In contrast some
organisms come in only one form and when they reproduce the progeny are
completely identical to the parents.25
Possible misconceptions:
Students confuse sexual reproduction with copulation and therefore may not
associate meiosis with sexual reproduction (CPRE, 2008).
Sub-cellular structures and diversity
Students have some understanding that
something inherent in living things
makes them different from non-living
things and they can identify many
living things from non-living things at a
very young age (NRC, 2007).
Some students will generally realize
plants are living.
Possible misconceptions:
Some students will have heard the term
germs – but may or may not associate
them with bacteria or viruses.33
Students may not recognize that
bacteria are cells or that they are living
Cell Biology and Biochemistry
Sub-cellular structures and diversity 34
Draw models of a few basic sub-cellular structures in cells: namely the cell
membrane, the nucleus, mitochondria, and the chloroplast.35
Possible misconceptions:
Students often confuse the relationship between a cell, a nucleus and biological
molecule like proteins and DNA. Students often do not realize that plants
undergo respiration like animals. (CPRE, 2008). Some students may
anthropomorphize cells and over-generalize thinking that the nucleus directs all
cell processes and that cells make decisions (NRC, 2007). Some students may
even think that some cells have little lungs or little stomachs (CPRE, 2008).
Students apply atomic molecular theory to living organisms and understand that
cells and all their sub-components are composed of molecules too (NRC, 2007).
[Link to atomic molecular theory]
Explain that bacteria must carry out all of the characteristics of life just like other
Massachusetts Department of Elementary and Secondary Education
Describe how the process of meiosis results in the
formation of haploid cells. Explain the importance of
this process in sexual reproduction, and how gametes
form diploid zygotes in the process of fertilization.
Compare and contrast mitosis and meiosis in terms
of the number of chromosomes at the beginning and
end of each cycle, and in what cell types from multicellular organisms these cellular processes occur.
Sub-cellular structures and diversity
Students know that there are a variety of sub-cellular
parts that have specific structures and do specific
functions for the cell. Sometimes these sub-cellular
structures come from outside the cell and use the sub
cellular structures of the cell to carry out their own
functions.
Draw models of structures one would find in a plant
cell and an animal cell if looked under a powerful
microscope: include sub-cellular parts/organelles
(e.g. plasma membrane, nucleus, cytoplasm,
mitochondrion, endoplasmic reticulum, Golgi
apparatus, ribosome, vacuole, cell wall, chloroplast,
cytoskeleton). Relate these structures to their
functions.37 Explain the role of cell membranes as a
highly selective barrier (diffusion, osmosis,
facilitated diffusion, and active transport). Predict
Cell Biology and Biochemistry
19
Cell Biology and Biochemistry
organisms (Driver et al., 1984) or that
they have DNA (CPRE, 2008).
November 15, 2010
living organisms, e.g. need to replicate (biosynthesize molecules), extract energy
from food (cellular respiration), get rid of waste, and respond to the
environment. Understand that bacteria have DNA.
Describe that viruses are smaller than bacteria and are not made of cells so they
need a host cell to replicate themselves.36 Recognize that viruses do not carry out
all the basic functions that cells do.
[Link to cell function above]
Possible misconceptions:
Students often do not appreciate the small size of viruses compared to cells (or
even tiny cells like bacteria). They may even confuse viruses and bacteria.
(Rogat, n.d.)
Before Instruction
Grades
Middle School
Key Vocabulary
Cell, molecule, atom, carbon, element, glucose, protein, DNA, trait, gene,
carbohydrate, food, energy, sugar, fat, burn, lipid, cell membrane, classification,
organism, chain links, cell function, transport, enzyme, growth, respiration,
unicellular, bacteria, sub-cellular, tissue, organ, system, nucleus, mitochondria,
chloroplast, atomic molecular theory, replicate, extract, waste, environment,
virus, host cell, chemical energy, carbon dioxide, sunlight, oxygen,
photosynthesis, chemical reaction, conservation of matter, energy
transformation, reproduce, multi-cellular, sperm, egg, fusion, cell division,
offspring, parent, progeny, identical
Cell Biology and Biochemistry
what would happen if one of these structures was
removed or ablated.38
Compare and contrast, at the cellular level, the
general structures and degrees of complexity of
prokaryotes and eukaryotes. Predict what structures
one would find if one looked under the microscope at
organisms from these two different kingdoms.
Compare and contrast different cell types from
animal and plant cells.
Compare and contrast a virus and a cell (in terms of
genetic material, structure and size, and reproduction,
and other basic requirement of living organisms).39
High School
Nucleic acid, RNA, organic molecule, amino acid,
nucleotides, hydrophobic, hydrophilic, dissolved,
biosynthesis, communication, channel protein,
ligand, receptor, cytoskeletal, digestion, metabolism,
pH, fungi, protist, organelle, plasma membrane,
cytoplasm, endoplasmic reticulum, Golgi apparatus,
ribosome, vacuole, cell wall, selective barrier,
diffusion, osmosis, active transport, ablated,
prokaryote, eukaryote, kingdom, ATP, cell cycle,
mitosis, meiosis, gamete, haploid, diploid zygote,
fertilization, chromosome
Notes
(1) Teachers should build from this in middle school and begin to ask students why they think they are important to be part of diet.
(2) There is very little research on middle school students understanding of proteins or structure of biological molecules. These intermediate understanding also require that middle
school students develop an atomic model of matter by the end of middle school; it does not have be an advanced model, but it is hypothesized that students need to relate and
distinguish the difference between an atom and a molecule and must realize all substances are composed of atoms and molecules—whether they are living or not.
(3) LIMIT: No detailed structures are expected to be understood or memorized. By high school should understand that proteins are basically a string of folded amino acids.
Ravit Duncan has evidence that middle school students can achieve some of the basic understanding of proteins described here.
(4) LIMIT: without much detail in description.
(5) LIMIT: But knowledge of this process is at a very limited level.
(6) So that they can realize can be broken down or built up from carbon atoms.
(7) LIMIT: Students should NOT be asked to memorize any structure in detail they should be able to recognize or describe the basic repeating units in these different types of
molecules and understand the big conceptual ideas about these molecules’ structure and function.
Massachusetts Department of Elementary and Secondary Education
Cell Biology and Biochemistry
20
Cell Biology and Biochemistry
November 15, 2010
Cell Biology and Biochemistry
(8) There is no evidence that this memorization of structure is helpful or beneficial. Any expectations for understandings about structure require prerequisite understanding of
chemistry- students must certainly be able to distinguish the difference between and an atom and a molecule. If structural understands are to be focused on, it is better to focus
on the fact that proteins are comprised of smaller carbon-based subunits, amino acids, that are chained together, and that nucleic acids are also comprised of smaller units that
are carbon based, nucleotides, that are carbon based. Finally lipids are comprised of long chain of carbon atoms. All have properties and structures that are key to their
function in cells. If student understand these larger molecules are comprised of smaller molecules they can understand the results and events in metabolism better and if this is
applied to proteins they can better understand how genes influence protein structure. Even though understanding the structure of DNA is critical to understanding how it is
replicated and how genes are expressed at a molecular level, students likely do not have to know these molecular mechanisms for an introductory biology class.
(9) LIMIT: We are not suggesting students memorized detailed molecular structures and properties, but instead understand a few basic chemical principles about biological
molecules and how they relate to their critical functions inside of cells. This is an elaboration of the existing idea about structures and functions. Both Ravit Duncan and Aaron
Rogat have evidence that high school student can learn these ideas in introductory biology in high school.
(10) They likely will not think of proteins as carrying out work inside of cells. But the teacher may be able to build from this understanding as a necessity of many living things.
(11) Pre-requisite knowledge: If breaking down food substances such as sugars are considered as exemplar work that proteins carry out, students must understand what chemical
reactions are at a molecular level (e.g. that they are a rearrangement of atoms to form new molecules making up substances [the LP proposed by Smith et al. 2006 for the
atomic molecular theory targets this understanding by the end of middle school]). Also, note that this idea also should connect to the digestion ideas in anatomy & physiology.
(12) Can expand later in high school.
(13) LIMIT: At this point the term enzyme does not have to be introduced, but the function of the chemical break-down of food substances inside of cells is a useful intermediate
understanding for students to develop – later in high school such molecular events can be associated with enzymes.
(14) This is noted as a potential misconception as there is no research citing this problem, mainly because middle school curriculum generally does not focus on proteins carrying
out work inside of cells. This is a predicted problem for students.
(15) In order to develop this idea, it is hypothesized that it is important for students to realize that chemical reactions take place in living organisms and that many biological
activities are chemical reactions (e.g. breaking down food into small molecules, assembling biological molecules). Students must have an atomic molecular model for matter
and understand that chemical reactions involve a rearrangement of atoms to form new substances with no atoms created or destroyed in the process.
(16) Proteins are not the only cellular molecules that carry out work in cells. Much research has pointed out the importance of RNA molecules in influencing cellular behavior and
function, many of which act as an enzyme. However, the vast majority of research on the cellular functions of cells over the last 50-60 years has focused on the role of
proteins. Thus understanding protein function is critical to developing a modern scientific view of how cells function.
(17) It is very important to connect ideas about protein structure and function with the genetics strand on regarding ideas that target DNA and gene function. Refer to genetics
strand for details about protein structure and function.
(18) Prediction-type learning performances are particularly effective to demonstrate students' level of understanding of this idea (e.g., if a critical structure of the enzyme is
changed, predict what will happen to its function).
(19) This anatomical understanding of how multi-cellular organisms are structured is a fundamental understanding and is key to understanding how and why changes in cell
function affect structures and functions at higher levels of organization.
(20) In this way students can begin to understand why glucose production is important to produce in plants and why photosynthesis is so important and special.
(21) LIMIT: Explain this as a transformation of energy from one type of chemical energy to another – but do not have to talk about ATP.
(22) Cellular respiration has to be linked to digestive and circulatory systems in anatomy & physiology so students understand where the sugar came from and how it is transported
to cells all over the body.
(23) It might be best to identify what is needed for growth in elementary school, but wait until students have some molecular understanding of substances at the end of middle
school before discussing photosynthesis or cellular respiration in any detail. There is abundant evidence that many students in middle school do not learn even the basics about
photosynthesis using a macroscopic view of matter. Some suggest that students cannot develop deep understanding of photosynthetic processes with out a decently developed
atomic molecular theory (NRC, 2007).
(24) It is hypothesized that students should be able to apply principles of conservation/transformation of energy in middle school to cellular respiration and photosynthesis (or other
biological chemical reactions) to understand the importance of ATP at high school. They might also need to understand what bonds are, thus a fairly sophisticated model of
matter needs to develop before learning about ATP in any deep way.
Massachusetts Department of Elementary and Secondary Education
Cell Biology and Biochemistry
21
Cell Biology and Biochemistry
November 15, 2010
Cell Biology and Biochemistry
(25) These understandings can be described or identified in texts, or using drawings, models, or pictures. These ideas about reproduction are likely in anatomy & physiology or
genetics progressions, but they are a prerequisite to understanding meiosis and mitosis in plants and animals.
(26) When describing and thinking about multi-cellular organisms be able to move between the cellular, tissue, and organ levels proficiently.
(27) This idea helps to support elaborate the ideas that some functions are carried out by all cells, but some functions are unique to some cells, this idea can also provide more
opportunities to explore the role of protein in cell function and how they support cell function. [This idea should also be linked to the anatomy strand]
(28) This performance is looking for the presence of multiple connected cells in students’ drawings of these different tissues; they do not have to be accurate—just looking for the
general understanding.
(29) It is critical for students to understand and apply conservation of matter here to both photosynthesis and cellular respiration (C. Anderson, personal communication).
(30) Only include this if you think student have the chemistry understanding to understand this as well the role of energy in rearranging molecules. Understanding of energy
transformations and conservation of energy is also important here. Without these understandings, students will have a very limited understanding of this concept.
(31) LIMIT: Students would not need to know detailed descriptions of the molecular mechanisms involved in generating ATP would be required however.
(32) LIMIT: Students do not need to memorize the every detailed step. Such memorization is likely to cause students to miss the big picture about the purpose and end results of
this mitosis. The same goes for meiosis.
(33) Not much here in the research.
(34) LIMIT: At middle school should focus on only a few sub-cellular structures and then add a few more structure in high school. I do not know of any evidence that focusing on
all the cell parts in middle school (or even high school) help student understand how cell work or function. ER and Golgi are important, but if students have no understanding
of proteins it is a waste of time. However, focusing on the nucleus as a storage place for DNA and the mitochondrion as a place to break down glucose and extract energy for
cell use—along with the cell membrane as a structure for regulating the flow or substance in and out of a cell, might all be appreciated -- even by middle school students.
Ultimately, even if proteins are understood by students as suggested above, I would still question the importance of talking about the Golgi and ER. Ribosomes are okay,
because they are structures for building proteins, so this understanding supports one of the basic functions of life that cells must carry out.
(35) Focus on plant and animal cells – and perhaps protists like paramecium.
(36) LIMIT: No need to understand details of this replication at this time.
(37) LIMIT: May include cilia or flagella but only if it supports understanding of another idea like the role of proteins in carrying out the work of cells.
(38) This is a unique way to get at structure function relationships without it being a memorization game which is less informative about student understanding.
(39) The main point here is that viruses can use DNA or RNA as a code to generate more copies, however a virus is much, much smaller than a cell and it is not a cell. In terms of
reproduction students must realize viruses are not self-sufficient and depend on a host cell to replicate while cells are self-sufficient and can reproduce on their own.
Authors and Reviewers
Dr. Aaron Rogat, Teachers College, Columbia University and the Consortium for Policy Research in Education (CPRE), New York (author)
Barbara C. Buckley, WestEd, California (reviewer)
References
American Association for the Advancement of Science (AAAS). (1993). Benchmarks for Science Literacy. Oxford University Press: New York.
Anderson, C. (n.d.). Personal communication.
Consortium for Policy Research in Education (CPRE). (2008). Pedagogical Content Knowledge Tools (PCK Tools). Cells and Organisms. University of Pennsylvania: Consortium
for Policy Research in Education.
Driver, R., Squires, A., Rushworth, P., & Wood-Robinson, V. (1994). Making sense of secondary science: Research into children’s ideas. London and New York: Routledge.
Duncan, R. (n.d.). Personal communication.
National Research Council (NRC). (2007). Taking Science To School: Learning and Teaching Science in Grades K-8. Eds. Duschl, R, Shweingruber, H. and Shouse, A. National
Academy Press: Washington DC.
Rogat, A. (n.d.), Unpublished data.
Massachusetts Department of Elementary and Secondary Education
Cell Biology and Biochemistry
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Cell Biology and Biochemistry
November 15, 2010
Cell Biology and Biochemistry
Smith, C. L., Wiser, M., Anderson, C. W., & Krajcik, J. (2006). Implications of research on children’s learning for standards and assessment: A proposed learning progression for
matter and atomic-molecular theory. Measurement: Interdisciplinary Research and Perspectives, 14(1-2), 1-98.
Massachusetts Department of Elementary and Secondary Education
Cell Biology and Biochemistry
23
Genetics
November 15, 2010
Genetics
Concept and Skill Progression for Genetics
Three models are represented within each grade span: 1) classical model of genetics; 2) cellular processes related to reproduction; and 3) the molecular aspects of genetics.
Additionally, the progression addresses five core ideas: 1) organization, location and function of DNA and genes; 2) relationships between genes, nuclear division, and passage of
genetic information; 3) effects of DNA mutations and variation; 4) gene variation and implications for phenotypic variation; and 5) transmission of genetic information and
patterns of inheritance. Core ideas 1 and 3 have specific relevance to molecular mechanisms, idea 2 relates specifically to cellular mechanisms, and ideas 4 and 5 relate to classical
genetics; these all eventually need be coordinated.
NARRATIVE STORYLINE
Initial Ideas
Before instruction students typically have a theory of inherited kinship; with this they can distinguish some inherited characteristics verses socially determined characteristics. They are,
however, likely to believe that daughters get their characteristics from mothers, and likewise sons from fathers. Students can identify some critical aspects of organisms required for
living, including the ability to reproduce. Students are also likely to understand that all living things share some of these things in common, as well as physical attributes. They are
unlikely, however, to attribute those to any common mechanism such as DNA or genes, even though they are likely to have heard about genes and DNA.
Conceptual Stepping Stones1
Elementary school students understand that siblings do not always look identical to each other or their parents, but have a combination of characteristics from their parents. They can
apply this to people, animals, and even reptiles or insects. They may, however, believe that plants are not living and therefore do not have genes. Students can identify critical aspects of
organisms needed to live, and know that genes somewhere inside living organisms provide information about an organism’s development. Students can explain that “information” in
genes about how organisms look provide are passed on from one generation to another. They do not, however, understand how this works.
Early middle school students understand that genes are linked to a theory of kinship. They know that traits are physical characteristics of organisms that are influenced by genes (e.g. “a
gene for eye color" is not actually an eye color, but has information about eye color). Students understand that mutations are changes in genetic information that can confer “different”
traits or functions. Students may associate reproduction with copulation and may believe it only occurs in animals. Students are able to explain that genes are inside cells, but may believe
they are in only a few cell types. Students understand that genes provide information about the development of traits or cellular entities, but likely believe genes are active “particles.”
Late middle school students understand the mechanism of how traits are passed between generations and relate kinship to genes. Students understand that genes are found in cells of all
organisms and associate genes with chromosomes. They can explain that chromosomes carry genetic information from generation to generation during cell division. Students understand
that for each trait we have two version of the gene (alleles). They understand that duplication of chromosomes occurs before cell division to maintain an equal amount of genetic
information. They know there are two types of cell division: mitosis and meiosis, but may not properly connect these to specific cell types. Students realize egg and sperm fuse in sexual
reproduction to produce a new cell that goes on to develop as the offspring. Students understand the role of genes in transmission of information and in influencing proteins and cell
function. They understand that a mutation in genes can result in a change in proteins or cell function.
Culminating Scientific Ideas2
High School students understand the relationship of genes to phenotypes. Students can explain how events during cell division are important in explaining why we see certain gene
combinations in predictable patterns. They understand only one copy of a trait needs to be present to show a dominant phenotype or both copies present to show a recessive phenotype.
They can predict possible combinations of alleles (and potential phenotypes) for the progeny of two parents with a given set of alleles. Students can relate DNA duplication and nuclear
division to the passage of DNA and consequently inherited traits. They understand that there are two types of division that cells can undergo (mitosis and meioses) and that these occur in
different cell types and result in different end products in terms of the number of chromosomes or genes produced. Students recognize that all organisms have DNA and genes. Students
can explain the role and function of genes in living organisms. They can relate and distinguish between chromosomes, genes, DNA, and nucleotides in animal and plant cells. They
understand the order of nucleotides in a gene determine the structure of a protein, and consequently the function of a protein in cells. Students can explain how a mutation in a gene can
affect the structure, function, or behavior of a cell or an organism by influencing the structure or function of proteins.
Massachusetts Department of Elementary and Secondary Education
Genetics
24
Genetics
November 15, 2010
Lower Anchor
Reflective of student concepts
Genetics
Upper Anchor
Reflective of science concepts
Reconceptualization
CONCEPT & SKILL DETAILS
Initial Ideas
Conceptual Stepping Stones
Culminating Scientific Ideas
Students who view the world in this way believe and can:
Students who fully understand this topic believe
and can:
3
Before instruction, students
often believe and can:
Pre-instruction
Organization and location
Possible Misconception:
While children will have
likely heard of the terms
DNA and genes from
media, and might develop
some associations with
these (see below), they
likely will think of them as
separate entities (Venville et
al, 2005) with separate
functions.
Gene function
Students are likely to have
heard of “genes” and “DNA.”
Students may believe that
genes are associated with a
theory of kinship (they might
say “it makes me look like
Grades PreK-4
Organization and
location
Students can explain that
genes are found
somewhere inside of
living organisms. Most
students will know that
mammals, and even
reptiles and insects, have
genes.
Possible Misconceptions:
Students often believe a
trait is the same as a gene
(Venville et al, 2005).
Students likely will not
believe that plants (or
other non-human
organisms, such as
bacteria or fungi; Shaw et
al, 2008) have DNA or
genes like humans do
(Lewis et al, 2000;
Venville et al, 2005).
Students may also
believe that non-living
object such as computer,
cars, or digital characters
like Digiman have DNA
(Venville et al, 2005).
Grades 5-6
Grades 7-8
Organization and location
Organization and location
Students are able to explain that
genes are inside cells of
organisms, but may believe they
are in only a few cell types like
brain and blood cells (Banet &
Ayuso, 2000).5 Students can
identify genes in a broader class
of organisms, including plants.
Also able to distinguish the
difference between a trait and a
gene, in other words know that a
gene corresponds to a physical
entity inside of cells, and traits
are physical characteristics of
organisms that genes influence
(e.g. “a gene for eye color" is not
actually an eye color, but it
influences the type of eye color
that is observed in an animal's
eye).
Students now understand that
genes are found inside of all
organisms and can associate genes
with chromosomes. Students can
identify genes in sex cells and
many other somatic cell types like
skin cells, muscle cells, and brain
cells.8 Students now understand
relative sizes of the entities (genes,
chromosomes, cells), including
molecular entities or those that
cannot be seen with the unaided
eye.9
[Link to PS atoms and molecules]
Massachusetts Department of Elementary and Secondary Education
Possible Misconceptions:
Students will likely confuse the
relationships between cells, atoms
and molecules (Flores et al, 2003).
They will likely confuse the
relationships between genes,
chromosomes, proteins, and cells
(Lewis et al, 2000; Marbach-Ad et
al, 2000; Rogat & Krajcik, n.d.).
High school
Organization, location and function of genes
and DNA
Students can relate and distinguish the
difference between DNA, nucleotides (and
their essential chemical components), genes,
and chromosomes in animal and plant cells.
Students understand that DNA is a long chain
of carbon-based molecules, of which specific
chemical subunits (nucleotides) in this chain
confer information. Students understand that
the DNA is packaged into chromosomes.11
The chromosomes are passed on from one
organism to another during reproduction, and
thus genes are passed on from one generation
to another.
Students recognize that all organisms, even
those without a nucleus like bacteria, have
DNA and genes.
Students can explain the role and function of
genes in living organisms. The order of
nucleotides in specific segments of DNA
provides information on how to build cellular
molecules, namely proteins, that do work in
cells (this is "genetic information"). These
segments of DNA are genes. Students must
understand the relationship of genes to
proteins and phenotypes (or variations in
traits, such as dark or light colored skin, or
the existence or absence of a disease such as
sickle cell anemia) (Duncan et al, 2009).
Genetics
25
Genetics
my parents”) and believe that
DNA is a unique
identification marker (such as
for crime scene investigations
so prevalent in media)
(Venville et al, 2005).
Possible Misconception:
Students may understand that
all living things share
something in common, but
are likely to focus on physical
attributes like the ability to
respond, move, or grow
(National Research Council,
2007) and are less likely to
think of DNA or genes as
common characteristics of all
living organisms (A. Rogat,
unpublished data)
Passage of genetic
information
Students typically know that
babies grow and are
delivered from within a
mother’s body; this insight
helps to develop a theory of
inherited kinship (Venville
et al, 2005). Students are
likely to know that progeny
in animals can be raised
inside of a mother’s “belly.”
Students at the age of 6 or 7
are likely to have a theory of
kinship and can distinguish
some inherited
characteristics verses
socially determined
characteristics (such as
language spoken or food
and clothes preferences)
November 15, 2010
Gene function
Students can explain that
genes provide
“information” about the
development of how
things look (Venville et
al, 2005). They might
apply this claim to a
limited number of
organisms. Genes are
seen as purely passing on
information from one
generation to another.4
Gene function
Students can explain that genes
provide information that affects
the development of physical
characteristics (traits), protein
structure and function, and
cellular activities and functions.6
Genetics
Gene function
Students are able to think about
genes in transmission of
information as coding for proteins
or other cellular molecules that
carry out the work of cells and
provide structure to cells.10
Possible Misconception:
Students likely believe genes are
active “particles” (Lewis &
Kattman, 2004).7
Passage of genetic
information
Students understand that
genes (or genetic
information) are passed
from generation to
generation, but do not
understand how. They
should have developed a
theory of kinship (i.e.
they understand that
young organisms born
from older organisms
will grow up to look like
older organisms, but
some characteristics such
as spoken language are
socially determined).
Passage of genetic information
Students can explain that
chromosomes (which carry genetic
information) are passed on from
generation to generation during cell
division (they relate kinship to genes
or DNA).z4 Students understand that
duplication of genetic information
prior to cell division helps to
maintain an equal amount of genetic
information in future generations;
students understand the mechanisms
of how traits are passed between
generations.
Students understand that for each
trait we have two version of the
gene (alleles).15
Cellular reproduction13
Students realize that cells divide
Massachusetts Department of Elementary and Secondary Education
Cellular reproduction
Students explain there are two
Passage of genetic information in living
organisms through cellular reproduction
Students understand how an organism is able
to pass on its physical characteristics to its
offspring. Students can relate DNA
duplication and nuclear division to the
passage of DNA and consequently inherited
traits. Students understand that DNA must be
duplicated prior to cell division19; this means
students must understand that a copy of the
DNA molecule is made and subsequently the
copy is passed on to a new cell (whether a
new sex cell such as an egg cell or sperm cell
or a new somatic cell such as a skin cell or an
intestinal cell). As such, students understand
the connection between chromosomes, genes,
and DNA (when DNA is copied and passed
on, so to are chromosomes that are made of
DNA and the genes that reside on
chromosomes). In this way the information in
DNA can be passed on to future generations.
Importantly in sexually reproducing multi-
Genetics
26
Genetics
November 15, 2010
(Venville et al, 2005),
although such
understandings are better
with human characteristics.
For example, students likely
would know an Asian baby
adopted by an Australian
Caucasian couple is likely to
grow up looking Asian as an
adult, but likely to speak
English and not an Asian
language.
Genome
Students can identify some
critical aspects of organisms
required for living, such as
ability to reproduce and take
in food for growth (National
Research Council, 2007).
to produce more cells; they do
not just spontaneously appear.
Possible Misconceptions:
Students typically fail to connect
cell division to the passage of
genetic information. The term
"cell division" may lead students
to develop a variety of models of
cell growth – some of which
preclude a model where the
ending products have the same
amount of material as the
starting cell (CPRE, 2008).
Students may associate
reproduction with copulation.
They may believe that it can
only occur in animals (CPRE,
2008).
Genome12
Students can identify most
of the critical aspects of
living organisms,
including the ability to
reproduce, harvest energy
from food, grow, and get
ride of waste.
Massachusetts Department of Elementary and Secondary Education
types of cell division: mitosis
occurs in most of the cells of the
body, and meiosis occurs in only
sex cells, like sperm and eggs.
Students may not, however,
properly connect these to specific
cell types inside of living
organisms (CPRE, 2008). They
can, however, relate these to stages
of the life cycle.16 Students can
identify the relative amount of
chromosomes or genes that result
from mitosis and meiosis (e.g. sex
cell produces cells each with half
the complement of chromosomes
or genes and other somatic cells
produce two identical cells with a
full complement of chromosomes
or genes). They realize in sexual
reproduction, egg and sperm fuse
to produce a new cell that goes on
to develop inside mother to
become a new baby. Students
realize that fertilization during
sexual reproduction restores a full
complement of chromosomes or
genes.17 Students appreciate that
sexual reproduction occurs in other
organisms like plants. Explain that
the existence of a cell indicates that
another cell existed previously –
cell division occurred which
produced an identical cell.
[Link to gene functions]
Genome
Students can associate physical
traits and functions of an organism
to genes. They recognize there are
tens of thousands of genes that
make up a genome in mammals.18
Genetics
cellular organisms only the DNA in a sex cell
(such as a sperm or egg cell) is of most
importance when considering passage of
heritable traits between parents and progeny,
and less important is the DNA in somatic
cells. However, the passage of genetic
information from cell to cell occurs any time
there is cell division in any somatic cell (such
as a skin cell, a brain cell, or a muscle cell).
Students can predict the number of
chromosomes or genes that a newly-divided
cell will contain.20 Students understand that
there are two types of division that cells can
undergo (mitosis and meioses) and that these
occur in different cell types and result in
different numbers of chromosome or genes
that are produced.
Students can explain why all the
chromosomes in an organism have to be
passed on to the next generation (whether a
single-cell or multi-cellular organism).
Students know that DNA must be duplicated
and passed on so the function of genes (such
as specifying proteins or other cellular
molecules) can influence physical
characteristics (Duncan et al, 2009). Students
understand the nature and role of the genome:
namely that all of the chromosomes and
corresponding genes in an organism together
influence all of the functions and behaviors
that a living organism must carry out to live
and survive, including basic functions like
harvesting energy from food molecules, or
building cellular molecules, or getting rid of
cellular waste products.21
[Link to Cell Biology and Biochemistry]
Genetics
27
Genetics
November 15, 2010
Mutations12
Possible Misconception:
The term “mutation” or
“mutant” (from popular
media) may have
negative connotations or
be associated with
negative outcomes.
Mutations
Students understand that
mutations are changes in genetic
information that can confer traits
or functions that are not normal.
Possible Misconception:
Students may believe mutations
can perhaps do good.
Gene variation and phenotypes
Students know that some how
genes are unique to a particular
individual and can pass that on
in order to pass on traits.
[Link to ‘traits can be passed
on’ and ‘theory of kinship’]
Mutations
Students understand that a
mutation in a gene can result in a
change in proteins which can
influence cell function.22
[Link to gene functions and
cellular reproduction]
Mutations
Students understand the order of nucleotides
in a gene determine the structure of a protein,
and consequently the function of a protein in
cells. Students can explain how a mutation in
a gene can affect the structure, function, or
behavior of a cell or an organism (i.e., its
phenotype) by influencing the structure or
function of cellular molecules such as
proteins. Students can relate changes in
protein function on cell function, structure, or
behavior at the molecular level. Students
understand that only mutations in gametes
(i.e. egg and sperm in animals) are passed on
to future generations.
[Link to genes, proteins, and phenotype]
Gene variation and phenotypes
Students can explain that gene
sequences can vary23 and can be
passed on to another generation,
and can explain that different gene
variations can affect protein or cell
function.24
Gene variation and phenotypes as related to
dominant and recessive traits
Students understand that the specific
nucleotide sequences of genes vary, ranging
from one small change in the nucleotide
sequence to large changes. Student can apply
their understanding about gene function to
understand the molecular and cellular
consequence of any changes to genes.
Students can connect DNA sequence
variation to the concept of alleles of genes,
and connect this to the role of genes in
influencing protein function, cell function,
and phenotype.
Dominant and recessive traits
Possible Misconceptions:
Students may associate the terms
“dominant” or “recessive” with
specific functions. For example,
Allchin (2002) notes the following
beliefs regarding dominance:
• Dominant traits are “stronger”
and “overpower” recessive
traits.
• Dominant traits are more likely
to be inherited.25
• Dominant traits are “better.”
• “Wild-type” or “natural” traits
are dominant, whereas mutants
are recessive.
Massachusetts Department of Elementary and Secondary Education
Genetics
Students can explain why a recessive allele
cannot have an effect on the phenotype of an
organism unless both alleles are of the same
variation (homozygous), while a dominant
allele can have an effect on the phenotype of
an organism when only one allele is present
(heterozygous). Students are also able to
explain that the nature of the interaction is
dependent on the type of variation in the gene
sequence for each allele present– and that
Genetics
28
Genetics
November 15, 2010
Genetics
• Male or masculine traits are
“dominant.”
Patterns of inheritance
Students are likely to
understand that sibling do
not always look identical to
each other or their parents,
but may have a combination
of traits.
Patterns of inheritance12
Students understand that
siblings do not always
look identical to each
other or their parents, but
may have a combination
of characteristics.
gene variations can result in abnormal,
dysfunctional, or absent gene products. With
this understanding, students can begin to
explain the molecular basis for dominant or
recessive alleles.
Patterns of inheritance
Students can predict all possible
combinations of alleles (and potential
phenotype) for the progeny of two parents
with a given set of alleles and predict the
frequencies of these combinations.26
Students can explain how events during cell
division are important to why certain gene
combinations are observed in predictable
patterns. Students can apply ideas of random
and equal distribution of alleles.27 Students
can explain that during sexual reproduction
chromosomes can recombine and segregate in
random ways, resulting in progeny that can
have different combinations of alleles—and
that this will determine the probability of
occurrence for any particular allele
combination, and consequently a particular
phenotype.
[Link to gene variation, meiosis, cell division
and passage of genetic information]
Possible Misconception:
Students are likely to
believe that daughters get
their traits from mothers,
and likewise sons from
fathers.
Grades
Pre-instruction
Grades PreK-4
Grades 5-6
Grades 7-8
High school
chromosome, somatic cell,
transmission, dominant, recessive,
protein, cell division, sex cell,
mitosis, meiosis, sexual
reproduction, fertilization, gene
variation, genome
allele, DNA, nucleotide, nucleus, phenotype,
genotype, nuclear division, gamete,
homozygous, heterozygous, DNA
duplication, DNA sequence,
Key Vocabulary
gene, organism,
characteristic, generation
cell, trait, class, function,
genome, mutation
Massachusetts Department of Elementary and Secondary Education
Genetics
29
Genetics
November 15, 2010
Genetics
Notes
(1) There is generally limited empirical evidence that suggests which intermediate ideas are productive stepping stones at each level. We have, however, evidence that students can
develop these ideas (citations noted). Also, these intermediate understandings address ideas for which we have some informed hypotheses that lead to the important ideas in the
targeted understanding. In many cases to move from an intermediate understanding to the targeted level of understanding all connections between ideas need to be consistently
made.
(2) Again the three models and five core ideas are represented in the storyline. These need to be connected in order to reach proficiency.
(3) In many cases there is little insight into student’s early ideas about genetics that are building blocks to later understanding. There is, however, research on naive conceptions,
some of which occur after students have some initial exposure to concepts in genetics.
(4) The notion of information as being passed on is not emphasized in most early curricula. "Information" at this level is about influencing the development of traits or perhaps
even how cells or organs function.
(5) Perhaps because students believe “inheritance” is passed on through the blood (a “blood relative”); Actually, mature mammalian red blood cells lack of nuclei and organelles,
do not contain DNA and cannot synthesize any RNA, and so cannot divide and have limited repair capabilities,.
(6) The idea that genes are informational is key. The basis for understanding how genes bring about physical traits lies in an understanding of genes as instructions for proteins.
Students need to develop basic understandings of the kinds of functions proteins have in cells in middle school. LIMIT: They do not need to understand the chemical structure
of proteins, but they should come to view proteins as “little machines” that either do work, or are structural components of the cell. Students will not be able to advance on
many of the concepts without these understandings.
(7) While “genes-as-particles” is not accurate, this thinking can be useful as long as students can build from it and this idea is confronted later in school.
(8) LIMIT: rare exceptions like mature red blood cells do not contain DNA or RNA.
(9) Chromosomes are viewable under a microscope and this can help anchor students’ understandings of the ideas of chromosomes, genes, and later DNA.
(10) LIMIT: but not yet describe molecular mechanisms consistently. There is some evidence that with appropriate instruction students can connect genes to protein function
(Duncan, unpublished results).
(11) LIMIT: Localization to nucleus is not essential, but can be covered if issues like cloning will be addressed.
(12) There is little current evidence for the particular intermediate stepping stones here; these are informed hypotheses.
(13) Students need to understand cells as the basis of life in order to understand concepts related to cell division. There is little current evidence for the particular intermediate
stepping stones here; these are informed hypotheses.
(14) Many students fail to connect cell division to passage of genetic information (Lewis and Wood-Robinson, 2000) or recognize the importance of duplication of genetic
materials (Riemeier & Gropengiesser, 2007). Students must make connections between these elements before high school.
(15) The idea that we have 2 versions of each gene (two alleles) because we have homologous chromosomes is at the crux of understanding the three genetic models. This is in no
way obvious or intuitive (why have 2 when you can get by with one?). It may not hold for all organisms but it holds for ones students are familiar with. Without an
understanding of the duplicate copies of genes they cannot understand meiosis or classical genetics. This should be introduced concurrently with the idea of halving the genetic
information in sex cells.
(16) Rather than a focus on the details of the process (the multitude of steps) there should be explicit attention to the purpose and outcome of these processes and how this relates to
the organism’s stage in the life cycle. Learning them out of this context is confusing for students as they don’t see a purpose to these processes.
(17) LIMIT: recombination is not part of this understanding until high school.
(18) Students likely will not, however, consider how the thousands of genes together influence all the inherited traits and critical life functions.
(19) LIMIT: students do not need to understand the details of DNA replication (transcription and translation).
(20) LIMIT: students do not need to explain how the numbers of chromosomes or genes are preserved through the division process.
(21) Genomic scientists have a good estimate of the number of genes in the human genome as a result of the human genome project (the current estimate is 20,000-25,000 genes),
but students do not need know the specific number. It is enough that they know the estimate to be tens of thousands of genes.
(22) Recent evidence suggests middle school students can get to the molecular or cellular level (Duncan, unpublished results).
(23) LIMIT: we would not expect students to understand the molecular nature of DNA at this age.
Massachusetts Department of Elementary and Secondary Education
Genetics
30
Genetics
November 15, 2010
Genetics
(24) LIMIT: but do not connect to concept of alleles until high school.
(25) This belief seems particularly problematic to developing ideas about the segregation and random assortment of alleles in high school.
(26) The Punnett square technique should not be the learning performance; the ability to think about potential genetic combinations and use that that to make predictions about the
occurrence of future phenotypes is the goal. Meiosis has to be connected to the resulting effects on the distribution of chromosomes and genes (Lewis and Wood-Robsinson,
2000) and to these Punnett square problems in order for students to “meaningfully” engage in these problems (Stewart, 1982).
(27) Students tend to attribute outcomes of an event that occurs due to random chance as the result of some causal or directive agent (Klymkowsky & Garvin-Goxas, 2008). This
may prevent them from incorporating ideas about random and independent assortment to the distribution of alleles between generations.
Authors and Reviewers
Dr. Aaron Rogat, Teachers College, Columbia University and the Consortium for Policy Research in Education (CPRE), New York (author)
Dr. Ravit Duncan, Rutgers University, New Jersey (reviewer)
References
Allchin, D. 2002. "Dissolving Dominance." Pp. 43-61 in Lisa Parker and Rachel Ankeny (eds.), Mutating Concepts, Evolving Disciplines: Genetics, Medicine, and Society.
Dordrecht: Kluwer.
Banet, E., & Ayuso, E. (2000). Teaching genetics at secondary school: A strategy about teaching the location of inheritance information. Science Education, 84, 313-351.
Consortirum for Policy Research in Education (CPRE). (2008) Science PCK Tool. (2008). University of Pennsylvania: CPRE, Philadelphia.
Duncan, R.D, Rogat, A.D., & Yarden, A. (2009) A Learning Progression for Deepening Students’ Understandings of Modern Genetics Across the 5th-10th grades. Journal of
Research in Science Teaching. 46(6): 655-674.
Duncan, R. Unpublished results. Rutgers University-New Brunswick, NJ.
Flores, F., Tovar, M., & Gallegos, L. (2003). Representation of the cell and its process in high school students: An integrated view. International Journal of Science Education,
25(2), 269-286.
Klymkowsky, M.W. & Garvin-Goxas, K. (2008, January). Recognizing Student Misconceptions through Ed's Tools and the Biology Concept Inventory. PLoS Biology. 6(1)e3.
Lewis, J. & Kattmann, U. (2004). Traits, genes, particles and information: Revisiting students' understanding of genetics. The International Journal of Science Education, 26, 195206.
Lewis, J., & Wood-Robinson, C. (2000). Genes, chromosomes, cell division and inheritance -- do students see any relationship? International Journal of Science Education, 22,
177 - 195.
Lewis, J., Leach, J. & Wood-Robinson, C. (2000). All in the genes? - Young people's understanding of the nature of genes. Journal of Biological Education, 34, 74-79.
Marbach-Ad, G., & Stavy, R. (2000). Students cellular and molecular explanations of genetic phenomena. Journal of Biological Education, 34, 200-210.
National Research Council. (2007). Taking science to school: Learning and teaching science in grades K-8. Washington DC: National Academy Press.
Riemeier, T., & Gropengiesser, H. (2007). On the roots of difficulties in learning about cell division: Process-based analysis of students’ conceptual development in teaching
experiments. International Journal of Science Education, 7, 1-17.
Rogat, A., & Krajcik, J. (n.d.). Unpublished results.
Shaw, K.R,M., Van Horne, K., Zhang, H. and Boughman, J. (2008). Essay Contest Reveals Misconceptions of High School Students in Genetics Content. Genetics, 178, 1157–
1168.
Stewart, J. (1982). Difficulties Experienced by High School Students when Learning Basic Mendelian Genetics. The American Biology Teacher. 44(2), 80-89.
Venville, G., Gribble, S., & Donovan, J. (2005). An Exploration of Young Children’s Understandings of Genetics Concepts from Ontological and Epistemological Perspectives.
Science Education. 89(4), 614-633.
Massachusetts Department of Elementary and Secondary Education
Genetics
31
Evolution & Biodiversity
November 15, 2010
Evolution & Biodiversity
Concept and Skill Progression for Evolution & Biodiversity
The progression is organized in four core ideas: fossils, morphology, and DNA can provide evidence of common ancestry among organisms; a species needs genetic variation to
survive and adapt; populations change due to natural selection and adaptation of many individuals; and biodiversity results from the formation of new species.
NARRATIVE STORYLINE
Initial Ideas
Before instruction students know there are different environments where animals and plants live.
Conceptual Stepping Stones
Early Elementary school students are able to observe and describe individual organisms and notice and describe qualitative variation within a population. Students are aware that
there are different environments with different climates that are home to specific types of animals and may be able to describe some characteristics of the animal that allow it to
live in that environment. They understand that fossils are evidence of animals and plants that lived long ago. Students are able to observe organisms and their attributes and can
describe changes brought about by growth. The can distinguish stages of growth of certain organisms. Children can measure heights of plants and lengths of caterpillars, use Venn
diagrams to reason about similarities and differences between moths and beetles, and represent change by successive differences of measures.
Late elementary school students understand that individuals of the same kind differ in their characteristics, and sometimes the differences give individuals an advantage in
surviving and reproducing. Students understand that structures perform functions that allow individuals to survive. Students can relate qualities of habitat and attributes of the
organisms living there. Students understand that changes in an environment can be detrimental to the organisms within it. Students make comparisons between characteristics of
fossils and those of living organisms and can infer what the environment was like of the organisms that lived long ago. Students engage in forms of argument that include
comparative analysis and modeling. Students are able to interpret change as difference between two measures: They can compare net change in more than one individual and
coordinate descriptions of change in counts or measures on two or more organisms or within attributes of the same organism. Students now include microorganisms as living
entities. Students can describe change over time mathematically (rate and changing rates) and characterize a measure (including units) based on a selected attribute.
Middle school students understand that biodiversity consists of different life forms (species) and they understand Earth consists of many biomes and ecosystems that support and
have influence on this variety of life. At this age students can distinguish between attributes and characteristics that are inherited through sexual or asexual reproduction and those
that are environmental. Students can explain how natural selection arises. Students understand that species that inhabit different habitats can have genetic variation, and they
understand species can change over generations and attribute this change to the specific beneficial traits of the individuals that survived to reproduce. Students understand
chronology and sedimentary rock deposition and relate placement of the fossil in the sedimentary layer to its age. Students are able to use mathematical and graphical constructs to
compare competing models of observed distribution and are able to relate statistics describing the distribution to biological events or processes and are able to develop competing
models for the same distribution of observed values. Students can interpret a graph or table of rate of change and are able to describe change using these measures.
Culminating Scientific Ideas
High school students understand that organisms reproduce to allow for the passing on of traits to successive generations. They understand that sexual reproduction provides a
source of genetic variation and can describe the various ways in which genetic variation comes about. They can explain that those individuals with characteristics that provide them
with some reproductive advantage over others in that particular environmental situation will survive to reproduce, whereas others will die. Students are able to explain that not all
offspring survive to reproductive age in part because of competition for resources. Students understand the relationship between biodiversity and extinction. They understand what
alleles are and how populations can change over time as frequencies of advantageous alleles increases. Students understand that natural selection can occur only if there is variation
in the genetic information between organisms of the same species in a population and variation in the expression of that genetic information as a trait. They are able to explain that
the similarities and differences in DNA sequences, anatomical evidence, and fossil evidence provide information about the branching sequence of lines of evolutionary descent.
They understand that advanced technologies have allowed scientists to compare DNA sequences of various organisms to infer lines of descent. Their methods of classification are
more sophisticated and so they are able to characterize various organisms as species and then classify species of organisms in groups (taxa) called clades to illustrate their common
ancestry. Students are able to provide a rational argument of how biological evolution explains the unity and diversity of species.
Massachusetts Department of Elementary and Secondary Education
Evolution & Biodiversity
32
Evolution & Biodiversity
November 15, 2010
Lower Anchor
Reflective of student concepts
Evolution & Biodiversity
Upper Anchor
Reflective of science concepts
Reconceptualization
CONCEPT & SKILL DETAILS
Initial Ideas
Conceptual Stepping Stones
Culminating Scientific Ideas
Before instruction, students
often believe and can:
Students who view the world in this way believe and can:
Students who fully understand this topic
believe and can:
Pre-instruction
K-2
3-5
6-8
High School
Evidence of Common
Ancestry
Evidence of Common
Ancestry
Evidence of Common Ancestry
Evidence of Common Ancestry
Evidence of Common Ancestry
Students can explain that fossils
provide evidence about plants
and animals that lived long ago.
(NRC, 2010)
Students understand that scientists
have identified many plants,
animals, and fungi.
Students can explain that thousands
of layers of sedimentary rock
provide evidence for the history of
the Earth changes in plants and
animals whose fossil remains are
found in the rock.
Students know that organisms
resemble their ancestors because
genetic information (DNA) is
transferred from ancestor to
offspring during reproduction.
(NRC, 2010)
Students understand that fossils are
remains or traces of organisms that
provide evidence of past life.
The similarities and differences on
DNA sequences, amino acid
sequences, anatomical evidence,
and fossil evidence provide
information about the branching
sequence of lines of evolutionary
descent. (NRC, 2010)
Students can explain that fossils
provide evidence about the types
of living organisms both visible
and microscopic, that lived long
ago and the nature of the
environments in which they lived.
(NRC, 2010)
Students can explain that fossils
can be compared to one another
and to living organisms according
to their similarities and differences.
(NRC, 2010)
Students know that the collection of
all fossils and their placement in
chronological order (e.g., dating or
location in sedimentary layers) is
known as the fossil record.
Students understand that because of
unique geological conditions that
are required for preservation, not all
organisms left fossils that can be
retrieved. (NRC, 2010)
Massachusetts Department of Elementary and Secondary Education
Students are able to organize
various collections of organisms
into taxa using phylogenetic data
and then organize species of
organisms into clades to infer their
common ancestry.
Evolution & Biodiversity
33
Evolution & Biodiversity
Genetic Variation
within a Species1 (NRC,
2010)
November 15, 2010
Evolution & Biodiversity
Genetic Variation within a
Species
Genetic Variation within a
Species
Genetic Variation within a
Species
Genetic Variation within a
Species
Students notice that there is
variation among living things of
one kind within a population
(NRC, 2010)
Students understand that
individuals of the same kind differ
in their characteristics, and
sometimes the differences give
individuals an advantage in
surviving and reproducing. (NRC,
2010)
Students understand that individuals
within a population vary on many
characteristics. Many, but not all of
these characteristics are inherited
(Lehrer & Schauble, 2010).
Students understand that sexual
reproduction not only allows the
continuation of traits in a population
but also provides a source of genetic
variation among the individuals of a
population through genetic
recombination. They also know that
variation within a population of
organisms can also result from
genetic mutations that create
variation in the expression of traits
between organisms of the same
species. (NRC, 2010)
Students are able to describe
qualitative differences in a
collection (Lehrer & Schauble,
2010).
Students are able to identify and
justify particular attributes by
selecting and characterize
attributes to be described (such
as wings or legs) and comparing
2 or more states of the same
attribute (Lehrer & Schauble,
2010).
Students are able to develop or
appropriate a measure of an
attribute and apply to a collection
(such as length of antennae or
width of wingspan) (Lehrer &
Schauble, 2010).
Possible Misconception:
Students typically explain
speciation using anthropomorphic
and teleological reasoning.
Students understand that individuals
(within a population) with certain
traits are more likely than others to
survive and have offspring. (NRC,
2010)
Students are able to structure a
collection of measures as a
distribution (such as beak length,
hand span, etc.) by displaying
measures of an attribute in a way
that makes aggregate properties in
the collection measurable, and by
using statistics that describe
qualities of the distribution, such as
central tendency or spread.2 (Lehrer
& Schauble, 2010).
Students are able to relate statistics
describing the distribution to
biological events or processes and
are able to develop models for the
same distribution of observed
values (Lehrer & Schauble, 2010).
Students are able to compare
competing models of observed
distribution and develop and apply
criteria for assessing relative fit and
validity of competing models
(Lehrer & Schauble, 2010).
Massachusetts Department of Elementary and Secondary Education
Students understand that directed
variation, called natural selection,
results (mostly) from habitat
variables3, and acts to bias
otherwise random genetic drift. The
interplay between random genetic
variation and directed variation is
the foundation of life’s diversity.
(Catley et al, 2005)
Students understand that natural
selection can occur only if there is
variation in the genetic information
between organisms of the same
species in a population and variation
in the expression of that genetic
information as a trait. Genetic
variation within a population
influences the likelihood that a
population will survive and
reproduce offspring. (NRC, 2010)
Evolution & Biodiversity
34
Evolution & Biodiversity
Change at the organism
and population level
through natural
selection and
adaptation1
November 15, 2010
Change at the organism and
population levels through
natural selection and
adaptation
Students understand that living
things can survive only in
environments in which their
needs are met. (NRC, 2010)
Students learn that the world has
many environments and distinct
environments support different
types of living things. (NRC,
2010)
Students are able to observe an
individual organism and describe
it at a given moment in time.
They can focus on present
condition or state (Lehrer &
Schauble, 2010).
Students are able to distinguish
distinct episodes of change and
represent them as stages (Lehrer
& Schauble, 2010).
Children are able to use
differences in measures of an
attribute to characterize growth.
For example, they compare
successive heights of a growing
plant or animal. They are able to
use these successive differences
to compare and represent the
growth patterns of two different
organisms of the same species or
two different organisms from
different species (Lehrer &
Schauble, 2010).4
Evolution & Biodiversity
Change at the organism and
population levels through
natural selection and
adaptation
Change at the organism and
population levels through
natural selection and adaptation
Change at the organism and
population levels through
natural selection and adaptation
Students understand that structures,
such as mouthparts or leaves,
perform functions that allow
individuals to survive. Structurefunction relations are the
cornerstone of adaptation. (Catley
et al, 2005)
Students can explain that natural
selection arises from three wellestablished observations: (1) There
is genetically-based variation in
traits within every species of
organism, (2) some of these traits
give some individuals advantage
over others in survival and
reproduction, and (3) those
individuals that survive to
adulthood will be more likely to
have offspring which will
themselves be more likely than
others to survive and reproduce.
Students are able to explain that not
all offspring survive to reproductive
age in part because of competition
for resources. Those individuals
with characteristics that provide
them with some reproductive
advantage over others in that
particular environmental situation
will survive to reproduce, whereas
others will die.
Children know that for any
particular environment, some kinds
of plants and animals survive well,
some survive less well, and some
cannot survive at all. (NRC, 2010)
Students understand that changes
in an organism’s habitat are
sometimes beneficial to it and
sometimes harmful. (NRC, 2010)
Possibility of Misconception
Students often think that organisms
are able to change themselves
within their lifetime (self-directed
design) because something has
changed in the environment or in
response to the organisms’
perceptions of need.
Students are able to develop
resemblance-based representations
of change of particular attributes
that support indirect comparison by
indexing change in one or more
attributes at two or more points in
time, but via verbal/textual
description or by representations
intended as copies; qualitatively
Massachusetts Department of Elementary and Secondary Education
Students are able to compare rates
of change across a population, or
compare the rates of change for
more than one organism by
describing change as rate or
changing rate; coordinating timeelapsed with counts or measures of
change, and determine the rate of
change; and interpreting a graph or
table of rate of change (Lehrer &
Schauble, 2010).
Students are able to invent derived
or composite measures and use the
measures to describe population
change by developing categories
that depend on representational
correspondence to measure change
over time; coordinating change in
one measured variable with change
in a measure of second measured
variable (multi-variate); describing
differing patterns of change and to
Natural selection leads to a diversity
of organisms that are anatomically,
behaviorally and physiologically
well-suited to survive and reproduce
in a specific environment. (NRC,
2010)
Students understand that
populations change over time as
frequencies of advantageous alleles
increases. These could accumulate
over time to result in speciation.5
Students understand that change
occurs at different scales of time
and organization: They understand
that the species and not the
organism is the unit of evolutionary
change; Growth refers to change in
single organisms or collections of
organisms within a lifespan. (Catley
et al, 2005)
Evolution & Biodiversity
35
Evolution & Biodiversity
November 15, 2010
comparing one or more copy-type
representations of the same
continuous attribute made at
different points in time; and
coordinating two or more
representations of change (Lehrer
& Schauble, 2010).
Students are able to describe
change based on count or
difference of one or more
measured attributes by interpreting
change as difference between two
measures; comparing net change in
more than one individual; and
coordinating descriptions of
change in counts or measures on
two or more organisms or within
attributes of the same organism
(Lehrer & Schauble, 2010).
Biodiversity
Evolution & Biodiversity
determine ratio of change in first to
change in second measure relative
to time; and interpreting graphs of
change in first measure to change in
second measure relative to time
(Lehrer & Schauble, 2010).
Students area able to coordinate,
compare and contrast different
models of change (multi-model) by
relating change in one model to
corresponding change in a second,
contrasting the affordances, and
explaining affordances and
limitations of different models
(Lehrer & Schauble, 2010).
Biodiversity
Biodiversity
Biodiversity
Students know there are different
kinds of places in the world that
represent different climates.
Students know that organisms and
populations of organisms live in a
variety of habitats. (NRC, 2010)
Students understand that biodiversity
consists of different life forms
(species) that have adapted to the
variety of conditions on Earth.
Biodiversity includes 1) genetic
variation within a species, 2) species
diversity in different habitats, and 3)
ecosystem diversity (e.g. forests,
grasslands, wetlands). (NRC, 2010)
Students are aware that there are
different kinds of plants and
animals live in different places
and need different things to live.
(NRC, 2010)
Biodiversity
Students understand that
biodiversity results from the
formation of new species
(speciation) minus extinction.
(NRC, 2010)
Grades
Pre-instruction
K-2
3-5
6-8
High School
Key Vocabulary
animal, plant, living, change,
environment, measure, growth
pattern, fossil, variation,
population, attribute, survive,
organism, stage, characteristic
habitat, microscopic, structure,
function, beneficial, harmful,
fungi, reproduce, antennae,
wingspan, leaf, adaptation,
representation
Massachusetts Department of Elementary and Secondary Education
trait, reproduction, biodiversity,
genetic variation, species, model,
sedimentary rock, chronological,
dating, geologic condition,
preservation, inherited, offspring,
distribution, statistic, natural
selection, variable, ecosystem
speciation, clade, extinction,
resource, anatomical, ancestor,
DNA, amino acid, taxa,
phylogentic, recombination,
mutation, bias, competition,
physiological, allele, scale
Evolution & Biodiversity
36
Evolution & Biodiversity
November 15, 2010
Evolution & Biodiversity
Notes
(1) Misunderstanding the distinction between individuals and species underpins many alternative conceptions of evolutionary processes. The use of clear, unambiguous and
consistent language when dealing with evolutionary education is critical. In particular, when teaching about individual organisms specify that individuals comprise a species or
population (part of a species). Further, when reference is made to collections of organisms; i.e. populations, species, or higher taxa, that these terms be consistently used. As the
species and not the organism is the unit of evolutionary change it is particularly important to make this clear. Taxon (taxa), a versatile but under-utilized term, can be correctly
used to denote any taxonomic category from species to phylum. Its use should be encouraged.
(2) Progress in describing population change is dependent on developing the mathematics needed to characterize distribution.
(3) Ecology’s role in evolution is pivotal for understanding natural selection, the means by which variability is directed.
(4) According to Schauble (in Catley et. al, 2005) understanding an attribute and understanding how to measure it are related ideas.
(5) Students may think that dominant alleles always increase in frequency from generation to generation, thinking that dominant alleles, over time, “dominate” recessive alleles out
of existence in a population, that the most abundant phenotype in a population represents the dominant trait, and that deleterious alleles will be eliminated quickly (Christensen,
2000). Gene pool frequencies are inherently stable; allele frequencies will remain unaltered indefinitely unless evolutionary mechanisms such as mutation and natural selection
cause them to change (Hardy -Weinberg Equilibrium Model). These concepts, however, are not typically addressed in high school biology.
Authors and Reviewers
Dr. Erin Marie Furtak, University of Colorado, Boulder, Colorado (contributor)
Dr. Leona Schauble, Vanderbilt University, Tennessee (contributor)
Sources
Anderson, D. L., Fisher, K. M., & Norman, G. J. (2002). Development and Evaluation of the Conceptual Inventory of Natural Selection. Journal of Research in Science Teaching,
39(10), 952-978.
Cately, K., Lehrer, R., & Reiser, B. (2005). Tracing a prospective learning progression for developing understanding of evolution. Paper commissioned by the National Academies
Committee on Test Design for K-12 Science Achievement. Center for Education, National Research Council.
Ferrari, M., & Chi, M. T. H. (1998). The nature of naive explanations of natural selection. International Journal of Science Education, 20(10), 1231-1256.
Lehrer, R., & Schauble, L. (2010). Seeding evolutionary thinking by engaging children: In modeling its foundations. Prepared for 2010 National Association for Research on
Science Teaching.
Mayr, E. (1997). This is Biology. Cambridge, MA: Harvard University Press.
McCormick, B. (2009). Modeling exponential population growth.(science experiment on natural selection and population dynamics )(Report) The American Biology Teacher. 71
(5), 291-294.
National Research Council (NRC; 2010). A Conceptual Framework for New Science Standards (Draft).
Shtulman, A. (2006). Qualitative differences between naive and scientific theories of evolution. Cognitive Psychology, 52, 170-194.
Massachusetts Department of Elementary and Secondary Education
Evolution & Biodiversity
37
Ecology
November 15, 2010
Ecology
Concept and Skill Progression for Ecology
The progression is organized in three core ideas: that there is a complex set of interactions within an ecosystem; that stability of ecosystems are determined by availability of
resources and habitat; and that the flow of matter and energy in an ecosystem obey the laws of physics and chemistry.
NARRATIVE STORYLINE
Initial Ideas
Before Instruction students may be able to associate organisms to certain physical locations and have some understanding that organisms have certain requirements for life.
They are not always able to distinguish living from non-living. Students understand that organisms “eat” one another, and they “eat” because they are hungry. Food is
considered everything that a plant or animal takes in including water, minerals, and, in the case of plants, carbon dioxide or even sunlight.
Conceptual Stepping Stones
Early Elementary students understand that humans and mammals are living organisms and can associate organisms to physical spaces with respect to general location. They
relate organisms to habitat via organism’s needs and ways of satisfying those needs. The relationship is perceived to be unidirectional; the habitat satisfies needs. Students
can explain that plants need air, water, and sunlight to grow but consider all of these components as plant food. At this age, the scientific definition of food is often confused
with its common usage. Students may think animals found lower in the food chain simply exist so that animals higher in the food chain can eat them.
Later Elementary students understand that the relationships between organisms and ecosystems are complex and interacting (bidirectional). They are able to distinguish
between abiotic and biotic components of a habitat and can begin to develop hypotheses about the mechanisms by which abiotic qualities of habitat (such as light & moisture)
affect resources required for survival. Students understand that the food of almost all kinds of animals can be traced back to plants. While students understand that people and
animals could not exist without plants, students think that plants undergo the process of photosynthesis just so we humans can breathe but they think of photosynthesis as a
type of respiration. Students still have difficulties understanding ideas about food, plant, and animal nutrition, and how this relates to the release of energy from food:
Students correctly understand that “energy is obtained from food” and have some basic understanding that food is broken down, that acid breaks down the food, and that
some kind of “goodness” is taken into the body from the food. However, the process that releases usable energy from food is unclear to students and is not related to the
chemical process of acquiring energy from food. Students see food chains as simple and linear.
Middle School students understand that organisms and populations of organisms are dependent on their interactions with other living things (biotic), and their interactions
with non-living (abiotic) factors in the environment, which together make up ecosystems. Students understand that ecosystems are complex and dynamic systems; however,
middle school students are not always able to distinguish between systems and cycles or to explain how they relate to ecosystem processes. Students are able to distinguish
types of interactions between organisms in a given environment as competitive or mutually beneficial and they understand the implications of these relationships to the
overall populations of the organisms. Middle school students understand that the basis of all food chains and food webs are organisms that create their own food from
processes such as photosynthesis. Students recognize the essential role of sunlight in photosynthesis and understand that all ecosystem processes rely on energy movement
from the sun to organisms
Culminating Scientific Ideas
High School students interpret food webs in terms of interconnected food chains and can describe energy transfer and conservation, as well as matter transfer and
transformation while accounting for the biotic and abiotic components in an ecosystem. Students understand food in terms of the chemical aspects of the carbohydrates,
proteins, and fats, which supply organisms’ cells with matter and energy to support life and can explain the principle that molecules travel in and through the organisms as
part of the world’s matter cycle. High School students are able to recognize the cyclical flow of matter and the interdependent relationship of organisms within an ecosystem
and are able to differentiate between systems and cycles while recognizing they are not mutually exclusive. Students understand photosynthesis as the process of
transforming light energy to chemical energy and stored in chemical compounds. Students are able to describe photosynthesis in terms of a process that leads to the storage of
energy in food and they understand that that the food provides energy for the plant’s life processes. Students understand that oxygen is simply a waste product of the process
of photosynthesis. Students understand energy transfer in the context of photosynthesis, respiration, and nutrition, and can describe how energy and matter are conserved.
Massachusetts Department of Elementary and Secondary Education
Ecology
38
Ecology
November 15, 2010
Ecology
CONCEPT & SKILL DETAILS
Lower Anchor
Reflective of student concepts
Upper Anchor
Reflective of science concepts
Reconceptualization
Conceptual “Stepping Stones”
Central Concepts & Skills
Students who view the world in this way believe and can:
Students who fully understand this topic
believe and can:
Before Instruction
Before instruction, students
often believe and can:
Pre-instruction
K-2
3-5
6-8
Interdependent
Relationships in Ecosystems
Students are able to consider
if an organism is alive and
where it lives. Students’
initial criteria for life are
based on overt resemblance
to familiar organisms,
especially people and pets;
Students judge humans and
mammals as living.
Interdependent relationships
in Ecosystems
Students are able to identify
organisms as functional units,
quantify what it means to
“eat” and “be eaten.”
Interdependent relationships in
Ecosystems
Students are able to identify and
qualitatively and quantitatively
describe a group/population of
organisms, noting either
similarities or differences.
Interdependent relationships in
Ecosystems
Students understand that populations
are made of individuals that live,
grow, reproduce, and die.
Students view organisms as
existing for the benefit of
humans.
Initial criteria for habitat are
based on analogy to home.
Students consider places
where living organisms are
seen as their homes.
Students associate
organisms to physical
spaces with respect to
general location (e.g.,
ground, air, pond, forest,
lawn).
Students can describe features
and/or behaviors of living and
non-living components of
places.
Students notice relative
frequencies of organisms in
one or more places.
Students expand criteria for
life to include ability to move
on its own, eating, and/ or
evidence of growth.
Students can observe
macroscopic attributes by use
of simple tools, such as hand
lens or dissecting scopes and
can describe the advantage of
macroscopic attributes that
allow the organism to use the
resources in a habitat
(behavior or structure).
Students notice that place or
time may be associated with
the presence or absence of
Students are able to describe
change within a group of
organisms by characterizing
transition in attributes, counts, or
stages.
Students are able to compare
organisms and their attributes
and their suitability to a habitat
and understand that organisms
can survive only in
environments in which their
needs are met. (NRC
Framework)
Students understand that the
relationships between organisms
and ecosystems are complex and
interacting (bidirectional) and
are able to describe ways in
which organisms affect
ecosystems by altering
ecosystem structures and
functions.
Students are able to characterize
Massachusetts Department of Elementary and Secondary Education
Students view organisms and
populations of organisms as
dependent on their interactions with
other living things (biotic), and their
interactions with non-living (abiotic)
factors in the environment. (NRC
Framework)
In any environment, organisms and
populations with similar
requirements for food, water, air, or
other resources may compete with
each other for limited resources. The
growth and reproduction of an
organism and of populations will be
constrained by access to these limited
resources. (NRC Framework)
The interactions between organisms
in a given environment may be
competitive or mutually beneficial.
Competitive interactions may reduce
the number of organisms or eliminate
populations of organisms. Mutually
beneficial interactions may become
so interdependent that each requires
the other for survival. (NRC
High school
Interdependent relationships in
Ecosystems
Students understand there are many
kinds of organisms in many different
places and this composition of life
changes over time.
Students understand organisms exist as
populations whose compositions
depend on history, biogeochemical
cycles, and space (geology).1
Students understand populations in
terms of species classifications.
Students understand that the factors
guiding the presence and absences of
organisms are complex and can be
linked to concepts of biodiversity,
evolution, biogeochemical cycles, and
geology.
Students know that a multitude of
organisms populate a particular habitat
and are embedded within a complex
system. They understand that what
affects one population of organisms is
also likely to affect the other
populations that live in that habitat.
Changes in habitat are apt to affect the
functioning of the ecology and thus the
chance that individual organisms will
survive and replicate. (Catley et al,
2005)
Ecology
39
Ecology
November 15, 2010
particular organisms.
Students understand that
animals depend on plants and
other animals for food.
Possible misconceptions
Students are able to consider
the needs of organisms but
students may relate organisms
to habitat via organism’s
needs and ways of satisfying
those needs. The relationship
is perceived to be
unidirectional; the habitat
satisfies needs.
interactions among organisms
and environments and are able to
develop hypotheses about the
mechanisms by which non-living
qualities of habitat (such as light,
moisture) affect resources
required for survival.
Students are able to describe,
measure, and model important
ecosystem components that are
not directly visible, such as
nutrients and microbes, and
climate.
When the environment changes,
some plants and animals survive
and reproduce; others move to
new locations, and some die.
(NRC Framework)
Framework)
Students are able to use multiple
resources to draw an ecosystem
(forest, desert, marine, stream, field,
or other) which includes organisms at
all trophic levels, and show how
these organisms interact.
Students understand are able to
characterize limits and their effects
on an ecosystem.
Students are able to describe how
disruptions to the physical (abiotic)
or biological (biotic) components of
an ecosystem impact other
components of an ecosystem. (NRC
Framework)
Students can represent adaptation as
a trade-off between costs and
benefits and relate this to change at
the organism level.
Possible misconception
Middle school students often conflate
systems and cycles as it relates to
ecosystem processes.
Flow of Matter and Energy
Transfer in Ecosystems
Children understand that
humans breathe oxygen and
they associate oxygen with
air.
Possible Misconceptions:
Young children think of
food as anything that is
edible.
Later, children think of food
as “anything taken into an
Flow of Matter and Energy
Transfer in Ecosystems
Living things get the materials
they need to grow and survive
from the environment.
(NRC Framework)
Many materials from living
things are used again by other
living things. (NRC
Framework)
Possible Misconceptions:
The scientific definition of
Flow of Matter and Energy
Transfer in Ecosystems
Students are able to explain that
food of almost all kinds of
animals can be traced back to
plants. Some animals eat plants
for food. Other animals eat
animals that eat plants.5 (NRC
Framework)
Students are able to represent
positions that an organisms
occupies in a food chain and the
interactions it has with other
Massachusetts Department of Elementary and Secondary Education
Flow of Matter and Energy Transfer
in Ecosystems
Students understand that all
ecosystem processes rely on energy
movement from the sun to organisms
Students can distinguish between
food chains and food webs: A food
chain is the transfer of energy from
primary producers (e.g. plants)
through a series of organisms that eat
and are eaten. A food web depicts
“the feeding relationships between
organisms in an ecosystem.; a series
Ecology
Students understand that ecosystems
have carrying capacities, which are
limits to the numbers and types of
organisms and populations an
ecosystem can support. These limits are
a result of such factors as availability of
biotic and abiotic resources, and biotic
challenges such as predation,
competition, and disease. (NRC
Framework)
Students understand and are able to
differentiate between systems and
cycles: systems are sets of interacting
components that operate on an
aggregate level to achieve a function.
Cycles are types of systems that repeat
(life cycle, carbon cycle, etc); however,
not all systems are cycles. Systems and
cycles are both dynamic.2
Students understand how to use
models, data visualization, control,
uncertainty, and multivariable study in
terms of ecosystem dynamics and
interactions.3
Flow of Matter and Energy Transfer in
Ecosystems
Students are able to explain that an
autotroph is able to create organic
compounds using simple nonorganic
molecules (e.g., carbon dioxide) using
energy (i.e., light or chemical
reactions).
Students understand that autotrophic
organisms start off food chains.
Students understand that autotrophic
organisms subsequently become food
for other animals to consume, which
Ecology
40
Ecology
organism’s body, including
water, minerals, and, in the
case of plants, carbon
dioxide or even sunlight”
(Driver, et al., 1994, p. 27).
Students have difficulty
with food webs, cycles, and
systems: Young students are
likely to think that feeding
relations are unidirectional:
they view an organism as
feeding on organisms but
not as being food for other
organisms. In the same
respect, they have difficulty
in considering each
organism is a food chain as
occupying more than one
role. (CPRE-PCK)
Young children think that
dead things just disappear;
they think of decomposition
as the total or partial
disappearance of matter.
November 15, 2010
food is often confused with its
common usage. In everyday
usage, “food is whatever
nutrients plants and animals
must take in if they are to
grow and survive.
Students understand that
plants absorb water from the
soil but may think that this is
the main process for growth
(Barker & Carr, 1989).
Students understand that
plants depend on air, water,
and light to grow but will
likely consider all these
components as well as heat
(from the sun), soil, minerals,
and fertilizer as food.4
Ecology
organisms: what an organism
eats, and what eats the organism.
of interconnected food chains
(CPRE-PCK)
can become food for other animals in
return. (CPRE-PCK)
Students understand that some
organisms such as fungi and
bacteria operate as decomposers.
Decomposition eventually
recycles some materials back to
the soil for plants to use, and to
repeat the food chain cycle.
(NRC Framework)
Students understand that light
contains energy and the light energy
captured by plants (producers) during
photosynthesis is utilized to facilitate
a chemical reaction between carbon
dioxide and water to produce sugar
and oxygen.7
Students understand that living things
are made up of essential elements, such
as oxygen, hydrogen, and carbon,
which combine to form biotic and
abiotic molecules such as proteins,
carbohydrates, and lipids, which are
vital to life processes.
Students are able to identify sugar as
food the photosynthetic organism has
created for itself and that this food is
used as both fuel and building
material.
Students understand energy is released
in chemical reactions during cellular
respiration in all organisms. In this
process that occurs in both plants and
animals, sugar molecules react with
oxygen molecules to produce water
molecules and carbon dioxide
molecules. In addition, during
respiration chemical energy is released
and can then be transformed into other
types of energy and used for a variety
of functions such as movement and to
build structures; Students are able to
trace carbon through ecosystems and
explain the multiple processes that are
involved in energy movement from the
sun to organisms and back to the
abiotic components.
Many children have some basic
understanding that food is
broken down, that acid breaks
down the food, and that some
kind of “goodness” is taken into
the body from the food; Students
understand the function of the
organs and have a “biological
basis” for understanding the
digestive system
Possible Misconceptions:
Students understand that “energy
is obtained from food” and
“digestion is the breakdown of
food,” but students can
misconceive that “digestion is
the process that releases usable
energy from food,” Students
confuse ideas about food, plant,
and animal nutrition, and
digestion and the release of
energy from food.6 (CPRE-PCK)
Students often think that plants
get their food from the soil. This
is a very common misconception
found by multiple researchers
and summarized by Bell (1985).
It is simply easier for students to
believe that roots are used for
feeding instead of coming to
Massachusetts Department of Elementary and Secondary Education
Students are able to explain that
oxygen is simply a waste product of
the process of photosynthesis rather
than something that is created just for
humans. (CPRE-PCK)
Students are able to define the terms
producer and consumer and relate
these terms to organisms and
connections drawn in a food web.
Students understand the biological
role of food- that food is used as fuel
and building material in all
organisms in a food chain. Plants
(producers), animals (consumers),
and decomposers use food (e.g.,
sugar, protein, fat) as a source of
energy and building material. Not all
food is converted to useful energysome dissipates as heat.
Students are able to describe, in
terms of energy, why there are only a
certain number of producers,
consumers, and top consumers in an
ecosystem. They are able to explain
from where the energy in the system
Students understand that matter and
energy are conserved in the food chain
including decomposition: the molecules
from the decomposed organisms
become part of the abiotic community
and are recycled. The flow of matter
and energy in a food chain obey the
laws of physics and chemistry.8
Possible Misconception:
Students view these changes brought
about by eating as a chemical processes
in which matter is transformed from
one type of substance to another during
Ecology
41
Ecology
November 15, 2010
understand that photosynthesis is
the process by which plants can
produce their own food.7
Students can confuse ideas of
plant photosynthesis and
respiration: many children have
a “`plant breathing-animal
breathing’ model: that animals
breathe in oxygen and breathe
out carbon dioxide, whereas
plants breathe in carbon dioxide
and breathe out oxygen” (Driver
et al., 1994, p. 33).7
Students are uncertain that a
gaseous element is a real
substance with mass and
weight—an essential notion in
understanding how plants use
carbon dioxide. (CPRE-PCK)
Students may think that plants
use heat (instead of light energy)
from the sun as the energy for
photosynthesis. Most students
considered that the sun is one
among “many sources of energy
for plants, others being soil,
minerals, water, air, and wind”
(Driver et al., 1994, p. 33).7
Ecology
originates and where each organism
acquires the energy and molecular
building blocks for life.
Possible Misconceptions:
Students may start out thinking that
respiration is an exchange of gases
involving only the lungs and the
heart but typically fail to link
respiration to metabolism or the
conversion of food to energy.
Students think that plants do not
respire or they respire only in the
dark and only through the pores of
their leaves. They do not think of
respiration in plants as an energy
conversion process. Students think
that photosynthesis is the energyproviding process of plants. 7
digestion, however, high school
students to have a limited
understanding of the role of food to
provide both energy and building
materials for the body.9 (CPRE-PCK)
Students typically fail to connect
chemical elements such as hydrogen,
oxygen, and carbon to the building
blocks upon which the body is built.
Due to this lack of understanding
about the chemical nature of life,
students think that rotted material
enriches or fertilizes the soil but they
don’t think of organic matter
changing to mineral matter during
decay or the role that microorganisms play as decomposers and
recyclers of essential elements of life.
Grades
Pre-instruction
K-2
3-5
6-8
High school
Abiotic, biotic, population, producer,
consumer, competitive, mutually
beneficial, interdependent, dynamic,
stability, resilience, photosynthesis,
respiration, metabolism, equilibrium,
system, cycle, molecule, atoms
Photosynthesis, respiration, catabolism,
dissipate, chlorophyll, chloroplast,
organelle, trophic level, autotrophic,
heterotrophic, chemical energy,
mechanical energy, conservation of
energy and matter
Key Vocabulary
Animal, plant, habitat
Organism, resource, bacteria,
fungi, decomposer, recycle,
ecosystem
Massachusetts Department of Elementary and Secondary Education
Ecology
42
Ecology
November 15, 2010
Ecology
Notes
(1) Geologic Processes. Understanding geologic processes is important for comprehending the time-scale involved in much of evolution/ecology and for developing
hypotheses about the course of evolution/ecological relationships. Geologic processes are key to developing descriptions of past environments and for reconstructing the
life history of the planet. (Catley et al, 2005)
(2) There are several domain general concepts students should understand. First, students should understand systems may change when components within the system
change. Second, cycles remain the same unless the system in which it is a component changes. Third, cycles are systems themselves. Ecosystems rely on naturally
evolved smaller-scale systems (e.g., the nitrification process in the aquaria) to achieve a function (e.g., in an aquaria, processing harmful substances from fish waste into
less harmful substances), which promotes stability because the cycle repeats.
(3) High School students should be aware of the work that ecologists do: Ecologists use models to not just represent but also to conceptualize and test ideas; Ecologists make
inferences based on large scales (across time and space); and ecologists work in a variety of experimental settings and use a variety of experimental techniques.
(4) Despite experiments in which students see germinating seeds and mature plants kept in the dark, this misconception seems to hold (Roth, Smith, & Anderson, 1983).
Many students equate sunlight to substances like water or minerals. As a result, many students fail to recognize the essential role of sunlight in photosynthesis.
(5) In scientific usage, food refers only to those substances, such as carbohydrates, proteins, and fats, from which organisms derive the energy they need to grow and operate
and the material of which they are made” (American Association for the Advancement of Science, 1993). Food is defined as those substances that provide energy and/or
building materials for organisms. (CPRE-PCK)
(6) According to Rowlands (2004), children at age 10 take a “mechanical” approach to understanding what happens to food after swallowing (p. 167). They see it as “being
contained inside a sack or tube in the body” and then as a “process of separation of useful parts of the food from non-useful parts, with the former being retained and the
latter got rid of as feces” Teixeira (2000) says that students at that same age understand the function of the organs and have a “biological basis” for understanding the
digestive system (p. 519). However, in both cases, students show no sign of understanding these changes as chemical processes in which matter is transformed from one
type of substance to another during digestion
(7) Photosynthesis is “so complex and completely different from the nutrition of animals” that we should not be surprised that these concepts should be confusing for students
(Wandersee, 1985, p. 593). Students are influenced by many experiences that do not support the scientific viewpoint, such as watering plants and talking about fertilizer as
“plant food.” Further, humans see themselves as the highest form of life on the planet, so remembering the importance of plants can be a challenge for students. Arnold
and Simpson (1980) in Driver et. al.,(1994, pg. 30) point out that students need to understand that “an element, carbon (which is solid in pure form), is present in carbon
dioxide (which is a colorless gas in the air) and that this gas is converted by a green plant into sugar (a solid, but in solution) when hydrogen (a gas) from water (a liquid)
is added using light energy which is consequently converted to chemical energy.” Students think of photosynthesis as a type of respiration. The terms breathing and
respiration were often used interchangeably, and oxygen is equated with air. They also believe that plants exchange gases primarily for the benefit of people. Students
need to understand that oxygen is simply a waste product of the process (Driver et al., 1994).
(8) Whether learning about photosynthesis, respiration, or catabolism (e.g., the building of biological molecules within cells), matter and energy are conserved. Thus, during
photosynthesis the carbon atoms in carbon dioxide are rearranged to produce sugar molecules, and during respiration the carbon atoms in sugars are rearranged to produce
carbon dioxide. No carbon atoms appear or disappear from existence in these processes. Energy is also conserved. Energy can be passed from one organism to another in
a food chain, through decay, or dissipate through heat, but it is never destroyed. (CPRE-PCK)
(9) Part of the problem may lay in the need for a more interconnected understanding of the topic of energy. Students encounter this topic in four biological contexts that are
essential to understanding feeding relations: photosynthesis, respiration, nutrition, and the interdependency of organisms. However, this version of energy is very
different from that studied in physics classes. Klein (1990) asserts that the subjects comprising ecology “cannot be contained within a single disciplinary framework”
(Eilam, 2002, p. 646). Concepts in ecology interact with concepts in physics such as equilibrium. Additionally, students must have a firm grasp of chemistry to
understand photosynthesis, though the concept generally is covered in biology. Just as plants, animals, humans, and even the sun interact with regard to nutrition, so too
do the differing branches of scientific study when we cover this broad set of topics. (CPRE-PCK)
Massachusetts Department of Elementary and Secondary Education
Ecology
43
Ecology
November 15, 2010
Ecology
Authors and Reviewers
Dr. Rebecca Jordan, Rutgers University, New Jersey (contributor)
David Mellor, Rutgers University, New Jersey (contributor)
Sources
American Association for the Advancement of Science. (1993). Benchmarks for ScienceLiteracy. NY: Oxford University Press.
Anderson, C. W. (2008, March). Learning Progressions for Environmental Science Literacy: Overview of the Interactive Poster Symposium. Presented at NARST annual
meeting.
Clement, J. (2000). Model based learning as a key research area for science education. International Journal of Science Education, 22, 1041-1053.
Consortium for Policy Research in Education (CPRE), PCK TOOLS.
Covitt, B., & Gunkel, K. (2008). Students’ developing understanding of water in environmental systems. Manuscript submitted for publication.
Eliam, B. (2002). Strata of comprehending ecology: Looking through the prism of feeding relations. Science Education, 86, 645-671.
Eisen, Y., & Stavy, R. (1988). Students’ understanding of photosynthesis. The American Biology Teacher, 50(4), 208-212.
Ferrari, M., & Chi, M. T. H. (1998). The nature of naive explanations of natural selection. International Journal of Science Education, 20, 1231-1256.
Grotzer, T. A., & Bell-Basca, B. (2003). How does grasping the underlying causal structures of ecosystems impact students' understanding? Journal of Biological Education, 38, 1628.
Hmelo, Silver, C. E. & Azevedo, R. (2006). Understanding complex systems: Some core challenges. Journal of the Learning Sciences, 15, 53-61.
Hogan, K. (2000) Assessing students’ systems reasoning in ecology. Journal of Biological Education, 35, 22-28.
Hogan, K. & Fisherkeller, J. (1996) Representing students’ thinking about nutrient cycling in ecosystems: Bidemensional coding of a complex topic. Journal of Research in
Science Teaching, 33, 941-970.
Hogan, K., Nastasi, B. K., & Pressley, M. (1999). Discourse patterns and collaborative scientific reasoning in peer and teacher-guided discussions. Cognition and Instruction, 17, 379432.
Hogan, K., & Weathers, K. C. (2003). Psychological and ecological perspectives on the development of systems thinking. In A. R. Berkowitz, C. H. Nilon & K. S. Hollweg (Eds.),
Understanding urban ecosystems: A new frontier for science and education (pp. 233-260). New York: Springer.
Jordan R. & R. Duncan (2006) Characterizing pre-service teacher understanding of the nature of science: two perspectives from two domains. Ecological Society of
America, Annual Meeting, Memphis TN.
Jordan, R, Singer, F., Vaughan, J., & Berkowitz A. (2008). What should every citizen know about ecology? Frontiers in Ecology and the Environment
Jordan, R., Gray, S., Demeter, M., Liu, L., & Hmelo-Silver, C. (2009) Promoting an Understanding of Ecological Concepts: A Review of Student Conflations of Ecological
Systems and Cycles. Applied Environmental Education and Communication.
Leach, J., Driver, R., Scott, P. & Wood-Robinson, C. (1996). Children's ideas about ecology 2: ideas found in children aged 5-16 about the cycling of matter. International
Journal of Science Education 18, 19-34.
Magtorn O. (2005). Student-teachers’ ability to read nature: reflections on their own learning in ecology. Int J Sci Ed 27: 1-25.
Mintzes, J. J., Trowbridge, J. E., Arnaudin, M. W., & Wandersee, J. H. (1991). Children's biology: Studies on conceptual development in the life sciences. In S. M. Glynn, R. H.
Yeany & B. K. Britton (Eds.), The psychology of learning science (pp. 179-202). Hillsdale NJ: Erlbaum.
National Research Council. (1996). National Science Education Standards. Washington D.C.: National Academy Press.
Ozkan, O., Tekkaya, C., & Geban, O. (2004). Facilitating conceptual change in students’ understanding of ecological concepts. Journal of Science Education and
Technology, 13, 95-105.
Perkins, D. N., & Grotzer, T. A. (2000). Models and moves: Focusing on dimensions of causal complexity to achieve deeper scientific understanding. Paper presented at the Presented
at the Annual Meeting of the American Educational Research Association, New Orleans LA.
Puk TG & Makin D. 2006. Ecological consciousness in Ontario elementary schools: the truant curriculum and the consequences. Appl Env Ed Com 5: 269-276.
Reiner, M. & Eliam, B. (2001). A systems view of learning. International Journal of Science Education, 23, 551-568.
Sabelli, N. (2006). Understanding complex systems strand: Complexity, technology, science, and education. The Journal of the Learning Sciences, 15, 5-9.
Massachusetts Department of Elementary and Secondary Education
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44
Ecology
November 15, 2010
Ecology
Schwarz, C. V. & White, B. Y. (2005). Metamodeling knowledge: Developing students’ understanding of scientific modeling. Cognition and Instruction, 23, 165-205.
Stavy, R., Eisen, Y., & Yaakobi, D. (1987). How students aged 13-15 understand photosynthesis. International Journal of Science Education, 9(1), 105-115.
Stone MK and Barlow Z (Eds) 2005. Ecological literacy: educating our children for a sustainable world. San Francisco: Sierra Club Books; Berkeley: Distributed by
University of California Press.
Teixeira, F. M. (2000). What happens to the food we eat? Children’s conceptions of the structure and function of the digestive system. International Journal of Science
Education, 22, 507-520.
Wandersee, J. H. (1985). Can the history of science help science educators anticipate student misconceptions? Journal of Research in Science Teaching, 23(7), 581-97.
Wilensky, U., & Resnick, M. (1999). Thinking in levels: A dynamic systems approach to making sense of the world. Journal of Science Education and Technology, 8, 3-19.
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