The Living Environment -- Learning Standard 1

(Retyped from the original by Stephen D. Klein/ Shenendehowa Schools, Clifton Park, N.Y. 12065)

 

Students will use mathematical analysis, scientific inquiry, and engineering design, as appropriate, to pose

                                    questions, seek answers, and develop solutions.

 

Science relies on logic and creativity.  Science is both a body of knowledge and a way of knowing – an intellectual and social process that applies human intelligence to explaining how the world works.  Scientific explanations are developed using both observations (evidence) and what people already know about the world (scientific knowledge).  All scientific explanations are tentative and subject to change.  Good science involves questioning, observing and inferring, experimenting, finding evidence, collecting and organizing data, drawing valid conclusions, and undergoing peer review.   Understanding the scientific view of the natural world is an essential part of personal, societal, and ethical decision making.   Scientific literacy involves internalizing the scientific critical attitude so that it can be applied in everyday life, particularly in relation to health, commercial, and technological claims.  Also see Laboratory Checklist in Appendix A.

 

                                                            Key Idea 1:

The central purpose of scientific inquiry is to develop explanations of natural phenomena in a continuing and creative process.

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Performance                  Elaborate on basic scientific and personal explanations of natural

Indicator 1.1          phenomena, and develop extended visual models and mathematical

                                    formulations to represent one’s thinking.

 

                                    Major Understandings

                                    1.1a            Scientific explanations are built by combining evidence that can be

observed with what people already know about the world.

 

1.1b            Learning about the historical development of scientific concepts or about individuals who have contributed to scientific knowledge provides a better under-standing of scientific inquiry and the relationship between science and society.

 

1.1c            Science provides knowledge, but values are also essential to making effective and ethical decisions about the application of scientific knowledge.

 

Performance         Hone ideas through reasoning, library research, and discussion with others,

Indicator 1.2           including experts.

 

                                    Major Understandings

1.2a            Inquiry involves asking questions and locating, interpreting, and processing information from a variety of sources.

 

                                    1.2b            Inquiry involves making judgments about the reliability of the source and

                                    relevance of information.

 

 

 

Performance         Work toward reconciling competing explanations;  clarify points of agreement

Indicator 1.3           and disagreement.

  

                          Major Understandings

1.3a            Scientific explanations are accepted when they are consistent with experimental and observational evidence and when they lead to accurate predictions.

 

                                    1.3b            All scientific explanations are tentative and subject to change or

improvement.  Each new bit of evidence can create more questions than it

answers.  This leads to increasingly better understanding of how things work in

the living world.

 

Performance        Coordinate explanations at different levels of scale, points of focus, and degrees of complexity and specificity, and recognize the     Indicator 1.4            need for such alternative representations of the natural world.

 

 

                                    Major Understandings

                                    1.4a      Well-accepted theories are ones that are supported by different kinds of scientific investigations often involving the contributions of individuals from different disciplines.

 

                                    Key Idea 2:         

 

Beyond the use of reasoning and consensus, scientific inquiry involves the testing of proposed explanations involving the use of conventional techniques and procedures and usually requiring considerable ingenuity.

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Performance          Devise ways of making observations to test proposed explanations.

Indicator 2.1           

 

Performance            Refine research ideas through library investigations, including electronic

Indicator 2.2           information retrieval and reviews of the literature, and through peer feedback obtained from review and discussion.

 

                                    Major Understandings

                                    2.2a      Development of a research plan involves researching background information and understanding the major concepts in the area being investigated.  Recommendations for methodologies, use of technologies, proper equipment, and safety precautions should also be included.

 

Performance                    Develop and present proposals including formal hypotheses to test explanations: 

Indicator 2.3           i.e., predict what should be observed under specific conditions if the explanation

is true.

 

                                    Major Understandings

                                    2.3a            Hypotheses are predictions based upon both research and observation.

 

                                    2.3b            Hypotheses are widely used in science for determining what data to

collect and as a guide for interpreting the data.

 

2.3c            Development of a research plan for testing a hypothesis requires

planning to avoid bias (e.g. repeated trials, large sample size, and objective data

collection techniques).

 

Performance                    Carry out a research plan for testing explanations, including selecting and

Indicator 2.4           developing techniques, acquiring and building apparatus, and recording

observations as necessary.

 

                                                            Key idea 3:

The observations made while testing proposed explanations, when analyzed using conventional and invented methods, provide new insights into natural phenomena.

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Performance          Use various methods of representing and organizing observations (e.g. diagrams,

Indicator 3.1          tables, charts, graphs, equations, matrices) and insightfully interpret the organized data.

 

                                    Major Understandings

                                    3.1a            Interpretation of data leads to development of additional hypotheses, the

formulation of generalization, or explanations of natural phenomena.

 

Performance          Apply statistical  analysis techniques when appropriate to test if chance alone

Indicator 3.2             explains the results.

 

Performance          Assess correspondence between the predicted result contained in the hypothesis and actual result, and reach a conclusion as to     Indicator 3.3         whether the explanation on which the prediction was based is supported.

 

Performance           Based on the results of the test and through public discussion, revise the explanation  and contemplate additional research.

Indicator 3.4 

                                    Major Understandings

                                    3.4a            Hypotheses are valuable, even if they turn out to be not true, because they

may lead to further investigation.

 

                                    3.4b            Claims should be questioned if the data are based on samples that are very

small, biased, or inadequately controlled or if the conclusions are based on the

faulty, incomplete, or misleading use of numbers.

 

                                    3.4c            Claims should be questioned if fact and opinion are intermingled, if

adequate evidence is not cited, or if the conclusions do not follow logically from the

evidence given.

 

 

Performance          Develop a written report for public scrutiny that describes the proposed explanation, including a literature review, the        
Indicator 3.5
             research carried out, its result, and suggestions for  further research.

 

                                    Major Understandings

                                    3.5a            One assumption of science is that other individuals could arrive at the same

explanation if they had access to similar evidences.   Scientists make the results of

their investigations public; they describe the investigations in ways that enable

others to repeat the investigations.

           

                                    3.5b            Scientists use peer review to evaluate the results of scientific investigations

and the             explanations proposed by other scientists.   They analyze the experimental

procedures, examine the evidence, identify faulty reasoning, point out statements

that go beyond the evidence, and suggest alternative explanations for the same

observations.

 

                                               

          The Living Environment -- Learning Standard 4

(Retyped from the revised Core Curriculum by Stephen Klein/ Shenendehowa H.S. Clifton Park, N.Y. 12065)

Students will understand and apply scientific concepts, principles, and theories pertaining to the physical

setting and living environment and recognize the historical development of ideas in science.

 

                                                Key Idea 1:

Living things are both similar to and different from each other and from nonliving things.

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Living things are similar in that they rely on many of the same processes to stay alive, yet are different in the ways that these processes are carried out.

 

Nonliving things lack certain features of living organisms, such as the ability to maintain a cellular organization, carry out metabolic processes while maintaining internal stability (homeostasis), and pass on heredity information through reproduction.

 

In most biological respects, humans are like other living organisms.  For instance, they are made up of cells like those of other animals, have much the same chemical composition, have organ systems and physical characteristics like many others, reproduce in a similar way, carry the same kind of genetic information system, and are part of a food web.

 

The components of living systems, from a single cell to an ecosystem, must interact to maintain balance.   Different organisms have different regulatory mechanisms regulatory mechanisms that function to maintain the level of organization necessary for life.  Diversity is evident and important at many levels of organization – from a single cell to a multicellular organism to an ecosystem.

 

Performance            Explain how diversity of populations within ecosystems relates to the stability of

Indicator 1.1           ecosystems.

 

                          Major Understandings

                                    1.1a            Populations can be categorized by the function they serve.  Food webs

identify the relationships among producers, consumers, and decomposers carrying

out either autotrophic or heterotrophic nutrition.

 

                                    1.1b            An ecosystem is shaped by the nonliving environment as well as its interacting

                                    species.  The world contains a wide diversity of physical conditions, which creates

                                    a variety of environments.

 

                                    1.1c            In all environments, organisms compete for vital resources.  The linked and chang-

                                    ing interactions of populations and the environment compose the total ecosystem.

 

                                    1.1d            The interdependence of organisms in an established ecosystem often results in

                                    approximate stability over hundreds and thousands of years.  For example, as one popu-

                                    lation increases, it is held in check by one or more environmental factors or another

                                    species.

 

                                    1.1e            Ecosystems, like many other complex systems, tend to show cyclic changes around

                                    a state of approximate equilibrium.

 

                                    1.1f            Every population is linked, directly or indirectly, with many others in an ecosys-

                                    tem.  Disruptions in the numbers and types of species and environmental changes can

                                    upset ecosystem stability.


 

Performance         Describe and explain the structures and functions of the human body at different

Indicator 1.2             organizational levels (e.g., systems, tissues, cells, organelles).

 

                                    Major Understandings

                                    1.2a      Important levels of  organization for structure and function include

                                    organelles, cells, tissues, organs, organ systems, and whole organisms.

 

 

                                    1.2b            Humans are complex organisms.  They require multiple systems for digestion,

                                    respiration, reproduction, circulation, excretion, movement, coordination, and immunity.

                                    The systems interact to perform the life functions.

 

                                    1.2c            The components of the human body, from organ systems to cell organelles,

                                    interact to maintain a balanced internal environment.  To successfully accomplish

                                    this, organisms possess a diversity of control mechanisms that detect deviations

                                    and make corrective actions.

 

                                    1.2d            If there is a disruption in any human system, there may be a corresponding

                                    imbalance in homeostasis.

 

                                    1.2e            The organs and systems of the body help to provide all the cells with their basic

                                    needs.  The cells of the body are of different kinds and are grouped in ways that

                                    enhance  how they function together.

 

                                    1.2f            Cells have particular structures that perform specific jobs.  These structures per-

                                    form the actual work of the cell.  Just as systems are coordinated and work together, cell

                                    parts must also be coordinated and work together.

 

                                    1.2g            Each cell is covered by a membrane that performs a number of important func-

                                    tions for the cell.  These include:  separation from its outside environment, controlling

                                    which molecules enter and leave the cell, and recognition of chemical signals.  The

                                    processes of diffusion and active transport are important in the movement of materials in

                                    and out of cells.

 

                                    1.2h            Many organic and inorganic substances dissolved in cells allow necessary

                                    chemical reactions to take place in order to maintain life.  Large organic food molecules

                                    such as proteins and starches must initially be broken down (digested to amino acids and

                                    simple sugars respectively), in order to enter cells.  Once nutrients enter a cell, the cell will

                                    use them as building blocks in the synthesis of compounds necessary for life.

 

                                    1.2i            Inside the cell a variety of specialized structures, formed from many different

                                    molecules, carry out the transport of materials (cytoplasm), extraction of energy from

                                    nutrients (mitochondria), protein building (ribosomes), waste disposal (cell membrane),

                                    storage (vacuole), and information storage (nucleus).

 

                                    1.2j            Receptor molecules play an important role in the interactions between cells.  Two

                                    primary agents of cellular communication are hormones and chemicals produced by

nerve cells.  If nerve or hormone signals are blocked, cellular communication is

disrupted and the organism's stability is affected.


Performance
            Explain how a one-celled organism is able to function despite lacking the levels of

Indicator 1.3             organization present in more complex organisms.

 

                                    Major Understandings

 

                                    1.3a            The structures present in some single-celled organisms act in a manner similar to

the tissues and systems found in multicellular organisms, thus enabling them to

perform all of the life processes needed to maintain homeostasis.

 

                                                                        Key Idea 2:

Organisms inherit genetic information in a variety of ways that result in continuity of structure and function between parents and offspring.

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Organisms from all kingdoms possess a set of instructions (genes) that determine their characteristics.  These

instructions are passed from parents to offspring during reproduction.  Students are familiar with simple mecha-

nisms related to the inheritance of some physical traits in offspring.  They are now able to begin to understand the molecular basis of heredity and how this set of instructions can be changed through recombination, mutation and genetic engineering.

 

The inherited instructions that are passed from parent to offspring exist in the form of a code.  This code is contained in DNA molecules.   The DNA molecules must be accurately replicated before being passed on.  Once the coded information is passed on, it is used by a cell to make proteins.  The proteins that are made become cell parts and carry out most functions of the cell.

 

Throughout recorded history, humans have used selective breeding and other biotechnological methods to produce products or organisms with desirable traits.  Our current understanding of DNA extends this to the manipulation of genes leading to the development of new combinations of traits and new varieties of organisms. 

 

Performance         Explain how the structure and replication of genetic material result in offspring that

Indicator 2.1           resemble their parents.

 

                                    Major Understandings

                                    2.1a      Genes are inherited, but their expression can be modified by interactions

                                    with the environment.

 

                                    2.1b      Every organism requires a set of coded instructions for specifying its traits.  For

                                    offspring to resemble their parents, there must be a reliable way to transfer information from one generation to the next.  Heredity is the passage of these instructions from one generation to another.

 

                                    2.1c      Hereditary information is contained in genes, located in the chromosomes of each

                                    cell.   An inherited trait of an individual can be determined by one or by many genes, and a single gene can influence more than one trait.  A human cell contains many thousands of different genes in its nucleus.

 

                                    2.1d            In asexually reproducing organisms, all the genes come from a single parent.

                                    Asexually produced offspring are normally genetically identical to the parent.

 

                                    2.1e            In sexually reproducing organisms, the new individual receives half of the genetic

                                    information from its mother (via the egg) and half from its father (via the sperm).  Sexually

                                    produced offspring often resemble, but are not identical to, either of their parents.

 

                                    2.1f            In all organisms, the coded instructions for specifying the characteristics of the

organism are carried in DNA, a large molecule formed from subunits arranged in a sequences with bases of four kinds (represented by A, G, C, and T).  The chemical and structural properties of DNA are the basis for how the genetic information that underlies heredity is both encoded in genes (as a string of molecular “bases”) and replicated by means of a template.

 

                                    2.1g            Cells store and use coded information.  The genetic information stored in DNA is

                                    used to direct the synthesis of the thousands of proteins that each cell requires.

 

                                    2.1h            Genes are segments of DNA molecules.  Any alteration of the DNA sequence is a

                                    mutation.  Usually, an altered gene will be passed on to every cell that develops from it.

 

2.1i            The work of the cell is carried out by the many different types of molecules it

assembles, mostly proteins.  Protein molecules are long, usually folded chains made from 20 different kinds of amino acids in a specific sequence.  This sequence influences the shape of the protein.  The shape of the protein, in turn, determines its function.

 

                                    2.1j            Offspring resemble their parents because they inherit similar genes that code for

                                    the production of proteins that form similar structures and perform similar functions.

 

                                    2.1k            The many body cells in an individual can be very different from one another, even

            though they are all descended from a single cell and thus have essentially identical genetic

             instructions.  This is because different parts of these instructions are used in different types

             of cells, and are influenced by the cell’s environment and past history.

 

Performance         Explain how the technology of genetic engineering allows humans to alter genetic

Indicator 2.2           makeup of organisms.

 

           

                                    Major Understandings

                                    2.2a            For thousands of years new varieties of cultivated plants and domestic animals

                                                have resulted from selective breeding for particular traits.

 

                                    2.2b            In recent years new varieties of farm plants and animals have been engineered by

                                                manipulating their genetic instructions to produce new characteristics.

 

                                    2.2c            Different enzymes can be used to cut, copy and move segments of DNA.

                                                Characteristics produced by the segments of DNA may be expressed when these

                                                segments are inserted into new organisms, such as bacteria.

 

                                   

                                    2.2d            Inserting, deleting, or substituting DNA segments can alter genes.  An altered

                                                gene may be passed on to every cell that develops from it.

 

2.2e            Knowledge of genetics is making possible new fields of health care; for example, finding genes which may have mutations that can cause disease will aid in the develop-ment of preventive measures to fight disease.  Substances, such as hormones and

enzymes, from genetically engineered organisms may reduce the cost and side effects of replacing missing body chemicals.

 

                                

                                                                        Key Idea 3:

Individual organisms and species change over time.

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Evolution is the change of species over time.  This theory is the central unifying theme of biology.   This change over time is well documented by extensive evidence from a wide variety of sources.  Students need to know that in sexu-ally reproducing organisms, only changes in the genes of sex cells can become the basis for evolutionary change  and that these evolutionary changes may occur in structure, function and behavior over time.  Students need to be able to distinguish between evolutionary change and the changes that occur during the lifetime of an individual organism.

 

According to many scientists, biological evolution occurs through natural selection.   Natural selection is the result of overproduction of offspring, variations among offspring, the struggle for survival, the adaptive value of certain variations, and the subsequent survival and increased reproduction of those best adapted to a particular environ-ment. Selection for individuals with a certain trait can result in changing the proportions of that trait in a population.

 

The diversity of life on Earth today is the result of natural selection occurring over a vast amount of geologic time for most organisms, but over a short amount of time for organisms with short reproductive cycles such as pathogens in an antibiotic environment and insects in a pesticide environment.

 

Performance         Explain the mechanisms and patterns of evolution.

Indicator 3.1          

                              Major Understandings

3.1a            The basic theory of biological evolution states that the Earth’s present-day species

developed from earlier, distinctly different species.

 

                                    3.1b            New inheritable characteristics can result from new combinations of existing

                                    genes or from mutations of genes in reproductive cells.

 

3.1c            Mutation and the sorting and recombining of genes during meiosis and fertil-ization result in a great variety of possible gene combinations.

 

3.1d            Mutations occur as random chance events.  Gene mutations can also be caused by such agents as radiation and chemicals.  When they occur in sex cells, the mutations can be passed on to offspring; if they occur in other cells, they can be passed on to other body cells only. 

 

3.1e            Natural selection and its evolutionary consequences provide a scientific explana-

tion for the fossil record of ancient life-forms, as well as for the molecular and structural

similarities observed among the diverse species of living organisms.

 

                                    3.1f            Species evolve over time.  Evolution is the consequence of the interactions of (1)

                                    the potential for a species to increase its numbers, (2) the genetic variability of offspring

                                    due to mutation and recombination of genes, (3) a finite supply of the resources required

                                    for life, and (4) the ensuing selection by the environment of those offspring better able to

                                    survive and leave offspring.

 

                                    3.1g            Some characteristics give individuals an advantage over others in surviving and

                                    reproducing, and the advantaged offspring, in turn, are more likely than others to survive

                                    and reproduce.  The proportion of individuals that have advantageous characteristics will

                                    increase.

                        3.1h            The variation of organisms within a species increases the likelihood that at least

                                    some members of the species will survive under changed environmental conditions.

 

Performance           3.1i            Behaviors have evolved through natural selection.  The broad patterns of behavior

Indicator  3.1          exhibited by organisms are those that have resulted in greater reproductive success.

 

                                   3.1j            Billions of years ago, life on Earth is thought by many scientists to have begun as

simple, single-celled organisms.  About a billion years ago, increasingly complex

multicellular organisms began to evolve.

 

3.1k            Evolution does not necessitate long-term progress in some set direction. 

Evolutionary changes appear to be like the growth of a bush; some branches survive from

the beginning with little or no change, many die out altogether, and others branch

repeatedly, sometimes giving rise to more complex organisms.

 

3.1l            Extinction of a species occurs when the environment changes and the adaptive

characteristics of a species are insufficient to allow its survival.  Fossils indicate that many

organisms that lived long ago are extinct.  Extinction of species is common; most of the

species that have lived on Earth no longer exist.

 

                                                Key Idea 4:

The  continuity of life is sustained through reproduction and development.

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Species transcend individual life spans through reproduction.  Asexual reproduction produces genetically identical offspring.  Sexual reproduction produces offspring that have a combination of genes inherited form each parent’s specialized sex cells (gametes).  The processes of gamete production, fertilization, and development follow an orderly sequence of events.   Zygotes contain all the information necessary for growth, development, and eventual reproduction of the organism.  Development is a highly regulated process involving mitosis and differentiation.  Reproduction and development are subject to environmental impact.  Human development, birth, and aging should be viewed as a predictable pattern of events.  Reproductive technology has medical, agricultural, and ecological applications. 

 

Performance                    Explain how organisms, including humans, reproduce their own kind.

Indicator 4.1

Major Understandings

4.1a            Reproduction and development are necessary for the continuation of any species.

 

4.1b            Some organisms reproduce asexually with all the genetic information coming from one parent.  Other organisms reproduce sexually with half the genetic information typically

contributed by each parent.  Cloning is the production of identical genetic copies.

 

4.1c            The processes of meiosis and fertilization are key to sexual reproduction in a wide

variety of organisms.  The process of meiosis results in the production of eggs and sperm

which each contain half of the genetic information.  During fertilization, gametes unite to

form a zygote, which contains the complete genetic information for the offspring.

 

4.1d            The zygote may divide by mitosis and differentiate to form the specialized cell,

tissues, and organs of multicellular organisms.

 

4.1e            Human reproduction and development are influenced by factors such as gene

expression, hormones, and the environment.  The reproductive cycle in both males and

females is regulated by hormones such as testosterone, estrogen, and progesterone.

         

4.1f            The structures and functions of the human female reproductive system, as in al-most all other mammals, are designed to produce gametes in ovaries, allow for internal fertilization, support the internal development of the embryo and fetus in the uterus, and

provide essential materials through the placenta, and nutrition through milk for the newborn.

 

4.1g            The structures and functions of the human male reproductive system, as in other

mammals, are designed to produce gametes  in testes and make possible the delivery of

these gametes for fertilization.

 

4.1h            In humans, the embryonic development of essential organs occurs in early stages

of pregnancy.  The embryo may encounter risks from faults in its genes and from its

mother’s exposure to environmental factors such as inadequate diet, use of

alcohol/ drugs/ tobacco, other toxins, or infections throughout her pregnancy.

 

                                                Key Idea 5:

Organisms maintain a dynamic equilibrium that sustains life.

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Life is dependent upon availability of an energy source and raw materials that are used in the basic enzyme-con-trolled biochemical processes of living organisms.  These biochemical processes occur within a narrow range of conditions.  Because organisms are continually exposed to changes in their external and internal environments, they must continually monitor and respond to these changes.  Responses to change can range in complexity from simple activation of a cell chemical process to elaborate learned behavior.   The result of these responses is called homeo-stasis, a “dynamic equilibrium” or “steady state” which keeps the internal environment within certain limits.  Organisms have a diversity of homeostatic feedback mechanisms that detect deviations from the normal state and take corrective actions to return their systems to the normal range.  These mechanisms maintain the physical and chemical aspects of the internal environment within narrow limits that are favorable for cell activities.  Failure of these control mechanisms can result in disease or even death.

 

Performance                    Explain the basic biochemical processes in living organisms and their importance in

Indicator  5.1          maintaining dynamic equilibrium.

 

                                    Major Understandings

                                    5.1a            The energy for life comes primarily from the Sun.  Photosynthesis provides a

                                    vital connection between the Sun and the energy needs of living systems.

 

5.1b            Plant cells and some one-celled organisms contain chloroplasts, the site of  photo-synthesis.  The process of photosynthesis uses solar energy to combine the inorganic

molecules carbon dioxide and water into energy-rich organic compounds (e.g., glucose) and release oxygen to the environment.

 

                                    5.1c            In all organisms, organic compounds can be used to assemble other molecules

                                    such as proteins, DNA, starch, and fats.  The chemical energy stored in bonds can be used

                                    as a source of energy for life processes.

 

            5.1d            In all organisms, the energy stored in organic molecules may be released during

            cellular respiration.  This energy is temporarily stored in ATP molecules.  In many organ-

            isms, the process of cellular respiration is concluded in mitochondria, in which ATP is

            produced more efficiently, oxygen is used, and carbon dioxide and water are released as

            wastes.


Performance                        5.1e            The energy from ATP is then used by the organism to obtain, transform, and

Indicator  5.1            transport materials, and to eliminate wastes.

 

continued                      5.1f            Biochemical processes, both breakdown and synthesis, are made possible by a

                                    large set of biological catalysts called enzymes.  Enzymes can affect the rates of chemical

                                    change.  The rate at which enzymes work can be influenced by internal environmental

                                    factors such as pH and temperature.

 

                                    5.1g            Enzymes and other molecules, such as hormones, receptor molecules, and

                                    antibodies, have specific shapes that influence both how they function and how they

                                    interact with other molecules.

 

Performance          Explain disease as a failure of homeostasis. 

Indicator 5.2

                              Major Understandings

                                    5.2a            Homeostasis in an organism is constantly threatened.  Failure to respond

                                    effectively can result in disease or death.

 

                                    5.2b            Viruses, bacteria, fungi, and other parasites may infect plants and animals and

                                    interfere with normal life functions.

 

                                    5.2c            The immune system protects against antigens associated with pathogenic

organisms or foreign substances and some cancer cells.

 

                                    5.2d            Some white blood cells engulf invaders.  Others produce antibodies that attack

                                    them or mark them for killing.   Some specialized white blood cells will remain, able to

fight off subsequent invaders of the same kind.

 

                                    5.2e            Vaccinations use weakened microbes (or parts of them) to stimulate the immune

                                    system to react.  This reaction prepares the body to fight subsequent invasions by the same

                                    microbes.

 

                                    5.2f            Some viral diseases, such as AIDS, damage the immune system, leaving the body

                                    unable to deal with multiple infectious agents and cancerous cells.

 

                                    5.2g            Some allergic reactions are caused by the body’s immune responses to usually

                                    harmless environmental substances.  Sometimes the immune system may attack

                                    some of the body’s own cells or transplanted organs.

 

                                    5.2h            Disease may also be caused by inheritance, toxic substances, poor nutrition,

                                    organ malfunction, and some personal behavior.  Some effects show up right away; others

                                    may not show up for many years.

 

                                    5.2i            Gene mutations in a cell can result in uncontrolled cell division, called cancer. 

                                    Exposure of cells to certain chemicals and radiation increases mutations and thus   increases

                                    the chance of cancer.

 

                                    5.2j            Biological research generates knowledge used to design ways of diagnosing,

                                    preventing, treating, controlling, or curing diseases of plants and animals.

 

Performance           Relate processes at the system level to the cellular level in order to explain dynamic 

Indicator 5.3           equilibrium in multicelled organisms. 

 

                                    Major Understandings

                                    5.3a            Dynamic equilibrium results from detection of and response to stimuli. Organisms

                                    detect and respond to change in a variety of ways both at the cellular level and at the

                                    organismal level. 

 

                                    5.3b            Feedback mechanisms have evolved that maintain homeostasis.  Examples include

                                    the changes in heart rate or respiratory rate in a response to increased activity in muscle

                                    cells, the maintenance of blood sugar levels by insulin from the pancreas, and the changes

                                    in openings in the leaves of plants by guard cells to regulate water loss and gas exchange.

 

                                                                        Key Idea 6:

Plants and animals depend on each other and their physical environment.

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The fundamental concept of ecology is that living organisms interact with and are dependent on their environment and each other.  These interactions result in a flow of energy and a cycling of materials that are essential for life.

 

Competition can occur between members of different species for an ecological niche.  Competition can also occur within species.  Competition may be for abiotic resources, such as space, water, air, and shelter, and for biotic resources such as food and mates.  Students should be familiar with the concept of food chains and webs.

 

Performance          Explain factors that limit growth of individuals and populations. 

Indicator 6.1

                              Major Understandings

                                    6.1a            Energy flows through ecosystems in one direction, typically from the Sun, through

                                    photosynthetic organisms including green plants and algae, to herbivores to carnivores and

                                    decomposers.

 

                                    6.1b            The atoms and molecules on the Earth cycle among the living and nonliving com-

ponents of the biosphere.  For example, carbon dioxide and water molecules used in

photosynthesis to form energy-rich organic compounds are returned to the environment

when the energy in these compounds is eventually released by cells.  Continual input of

energy from sunlight keeps the process going.  This concept may be illustrated with an

energy pyramid. 

 

                                    6.1c            The chemical elements, such as carbon, hydrogen, nitrogen, and oxygen, that make

                                    up the molecules of living things pass through food webs and are combined and recom-

bined in different ways.  At each link in a food web, some energy is stored in newly made

structures but much is dissipated into the environment as heat.

 

                                    6.1d            The number of organisms any habitat can support (carrying capacity) is limited by

                                    the available energy, water, oxygen, and minerals, and by the ability of ecosystems to

                                    recycle the residue of dead organisms through the activities of bacteria and fungi.

 

                                    6.1e            In any particular environment, the growth and survival of organisms depend on the

                                    physical conditions including light intensity, temperature range, mineral availability,  soil/rock type, and relative acidity (pH).

 

 

Performance            6.1f            Living organisms have the capacity to produce populations of unlimited size, but

Indicator                   environments and resources are finite.  This has profound effects on the interactions

among organisms.

 

                                    6.1g            Relationships between organisms may be negative, neutral, or positive.  Some

                                    organisms may interact with one another in several ways.  They may be in a

                                    producer/consumer, predator/prey, or parasite/host relationship; or one organism may

                                    cause disease in, scavenge, or decompose another.

 

Performance         Explain the importance of preserving diversity of species and habitats. 

Indicator 6.2

                              Major Understandings

                                    6.2a            As a result of evolutionary processes, there is a diversity of organisms and roles in

                                    ecosystems.  This diversity of species increases the chance that at least some will survive

                                    in the face of large environmental changes.  Biodiversity increases the stability of the

                                    ecosystem.

 

                                    6.2b            Biodiversity also ensures the availability of a rich variety of genetic material that

                                    may lead to future agricultural or medical discoveries with significant value to

humankind.   As diversity is lost, potential sources of these materials may be lost with it.

 

Performance         Explain how the living and nonliving environments change over time and respond to  

Indicator 6.3          disturbances.

 

                                    Major Understandings

                                    6.3a            The interrelationships and interdependencies of organisms affect the development

                                    of stable ecosystems.

 

                                    6.3b            Through ecological succession, all ecosystems progress through a sequence of

                                    changes during which one ecological community modifies the environment, making it

                                    more suitable for another community.  These long-term gradual changes result in the

                                    community reaching a point of stability that can last for hundreds or thousands of years.

 

6.3c            A stable ecosystem can be altered, either rapidly or slowly, through the activities of organisms (including humans), or through climatic changes or natural disasters.  The

                                    altered ecosystem can usually recover through gradual changes back to a point of long-

                                    term stability.

 

 

                                                                        Key Idea 7:

Human decisions and activities have had a profound impact on the physical and living environment.

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Population growth has placed new strains on the environment – massive pollution of air and water, deforestation and extinction of species, global warming, and alteration of the ozone shield.  Some individuals believe that there  will be a technological fix for such problems.  Others, concerned with the accelerating pace of change and the ecological concept of finite resources, are far less optimistic.  What is certain, however, is that resolving these issues will require increasing global awareness, cooperation, and action. 

 

Since the students of today will be the elected officials and informed public of tomorrow, the teacher should encourage a diversity of activities that will allow students to explore, explain, and apply conceptual understanding and skills necessary to be environmentally literate. 

 

Performance           Describe the range of interrelationships of humans with the living and nonliving 

Indicator 7.1           environment.

 

                                    Major Understandings

                                    7.1a            The Earth has finite resources; increasing human consumption of resources places

                                    stress on the natural processes that renew some resources and deplete those resources

that cannot be renewed.

                                   

                                    7.1b            Natural ecosystems provide an array of basic processes that affect humans.  Those

                                    processes include but are not limited to: maintenance of the quality of the atmosphere,

                                    generation of soils, control of the water cycle, removal of wastes, energy flow, and recy-

cling of nutrients.  Humans are changing many of these basic processes and the changes

may be detrimental. 

 

                                    7.1c            Human beings are part of the Earth’s ecosystems. Human activities can, deliberate-

ly or inadvertently, alter the equilibrium in ecosystems.  Humans modify ecosystems as a

result of population growth, consumption, and technology.  Human destruction of habitats

through direct harvesting, pollution, atmospheric changes, and other factors is threatening

current global stability, and if not addressed, ecosystems may be irreversibly affected.

 

Performance           Explain the impact of technological development and growth in the human population on 

Indicator 7.2           the living and nonliving environment.

 

                                    Major Understandings

                                    7.2a            Human activities that degrade ecosystems result in a loss of diversity of the living

                                    and nonliving environment.  For example, the influence of humans on other organisms

                                    occurs through land use and pollution.  Land use decreases the space and resources

                                    available to other species, and pollution changes the chemical composition of air, soil,

and water.

 

                                    7.2b            When humans alter ecosystems either by adding or removing specific organisms,

                                    serious consequences may result.  For example, planting large expanses of one crop

                                    reduces the biodiversity of the area.

 

                                    7.2c            Industrialization brings an increased demand for and use of energy and other

resources including fossil and nuclear fuels.   This usage can have positive and negative

effects on humans and ecosystems. 

 

Performance           Explain how individual choices and societal actions can contribute to improving the

Indicator 7.3           environment.

 

                                    Major Understandings

                                    7.3a            Societies must decide on proposals which involve the introduction of new

                                    technologies.  Individuals need to make decisions which will assess risks, costs, benefits,

                                    and trade-offs. 

 

7.3b            The decisions of one generation both provide and limit the range of possibilities

open to the next generation.

 

The Living Environment                    Appendix  A

 

In addition to demonstrating the performance indicators relating to scientific inquiry described in Standard1, biology students need to develop proficiency in certain laboratory or technical skills in order to successfully conduct investigations in biological science.   During the school year, teachers should ensure that students develop the capacity to successfully perform each of the laboratory skills listed below.  Proficiency in performing these laboratory skills may also be evaluated by items found on certain parts of the State’s Living environment assessment. 

 

·        Follows safety rules in the laboratory

 

·        Selects and uses correct instruments

·        Uses graduated cylinders to measure volume

·        Uses metric ruler to measure length

·        Uses thermometer to measure temperature

·        Uses triple-beam or electronic balance to measure mass

 

·        Uses a compound microscope/stereoscope effectively to see specimens clearly, using different magnifications

·        Identifies and compared parts of a variety of cells

·        Compares relative sizes of cells and organelles

·        Prepares wet-mount slides and uses appropriate staining techniques

 

·        Designs and uses dichotomous keys to identify specimens

 

·        Makes observations of biological processes

 

·        Dissects plant and/ or animal specimens to expose and identify internal structures

 

·        Follows directions to correctly use and interpret chemical indicators

 

·        Uses chromatography and/ or electrophoresis to separate molecules

 

·        Designs and carries out a controlled, scientific experiment based on biological processes

 

·        States an appropriate hypothesis

 

·        Differentiates between independent and dependent variables

 

·        Identifies the control group and/ or controlled variables

 

·        Collects, organizes, and analyzes data, using a computer and/or other laboratory equipment.

 

·        Organizes data through the use of data tables and graphs

 

·        Analyzes results from observations/ expressed data

 

·        Formulates an appropriate conclusion or generalization from the results of an experiment.

 

·        Recognizes assumptions and limitations of the experiment.