PERFORMANCE INDICATOR 1.1: Explain how diversity of populations within ecosystems relates to the stability of ecosystems.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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 population increases, it is held in check by one or more environmental factors or another species.

MAJOR UNDERSTANDING 1.1e: Ecosystems, like many other complex systems, tend to show cyclic changes around a state of approximate equilibrium.

MAJOR UNDERSTANDING 1.1f: Every population is linked, directly or indirectly, with many others in an ecosystem. Disruptions in the numbers and types of species and environmental changes can upset ecosystem stability.

Key Idea 2: Organisms inherit genetic information in a variety of ways that result in continuity of structure and function between parents and offspring.

PERFORMANCE INDICATOR 2.1: Explain how the structure and replication of genetic material result in offspring that resemble their parents.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 2.1d: In asexually reproducing organisms, all the genes come from a single parent. Asexually produced offspring are normally genetically identical to the parent.

MAJOR UNDERSTANDING 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.

Key Idea 3: Individual organisms and species change over time.

PERFORMANCE INDICATOR 3.1: Explain the mechanisms and patterns of evolution.

MAJOR UNDERSTANDING 3.1a: The basic theory of biological evolution states that the Earth’s present-day species developed from earlier, distinctly different species.

MAJOR UNDERSTANDING 3.1b: New inheritable characteristics can result from new combinations of existing genes or from mutations of genes in reproductive cells.

MAJOR UNDERSTANDING 3.1c: Mutation and the sorting and recombining of genes during meiosis and fertilization result in a great variety of possible gene combinations.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 3.1e: Natural selection and its evolutionary consequences provide a scientific explanation 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.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 3.1i: Behaviors have evolved through natural selection. The broad patterns of behavior exhibited by organisms are those that have resulted in greater reproductive success.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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.

PERFORMANCE INDICATOR 4.1: Explain how organisms, including humans, reproduce their own kind.

Key Idea 6: Plants and animals depend on each other and their physical environment.

PERFORMANCE INDICATOR 6.1: Explain factors that limit growth of individuals and populations.

MAJOR UNDERSTANDING 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).

MAJOR UNDERSTANDING 6.1f: Living organisms have the capacity to produce populations of unlimited size, but environments and resources are finite. This has profound effects on the interactions among organisms.

PERFORMANCE INDICATOR 6.2: Explain the importance of preserving diversity of species and habitats.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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 INDICATOR 6.3: Explain how the living and nonliving environments change over time and respond to disturbances.

MAJOR UNDERSTANDING 6.3a: The interrelationships and interdependencies of organisms affect the development of stable ecosystems.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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 longterm stability.

Key Idea 7: Human decisions and activities have had a profound impact on the physical and living environment.

PERFORMANCE INDICATOR 7.1: Describe the range of interrelationships of humans with the living and nonliving environment.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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 recycling of nutrients. Humans are changing many of these basic processes and the changes may be detrimental.

MAJOR UNDERSTANDING 7.1c: Human beings are part of the Earth’s ecosystems. Human activities can, deliberately 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 INDICATOR 7.2: Explain the impact of technological development and growth in the human population on the living and nonliving environment.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 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 INDICATOR 7.3: Explain how individual choices and societal actions can contribute to improving the environment.

MAJOR UNDERSTANDING 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.

MAJOR UNDERSTANDING 7.3b: The decisions of one generation both provide and limit the range of possibilities open to the next generation.

Key Idea 1: Living things are both similar to and different from each other and from nonliving things.

KEY IDEA 1: The central purpose of scientific inquiry is to develop explanations of natural phenomena in a continuing and creative process

PERFORMANCE INDICATOR 1.2: Hone ideas through reasoning, library research, and discussion with others, including experts

PERFORMANCE INDICATOR 1.3: Work towards reconciling competing explanations; clarify points of agreement and disagreement

KEY IDEA 3: The observations made while testing proposed explanations, when analyzed using conventional and invented methods, provide new insights into natural phenomena.

PERFORMANCE INDICATOR 3.1: Use various methods of representing and organizing observations (e.g. diagrams, tables, charts, graphs, equations matrices) and insightfully interpret the organized data

PERFORMANCE INDICATOR 3.2: Apply statistical anaysis techniques when appropriate to test if chance alone explains the results

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

Follows safety rules in the laboratory

States an appropriate hypothesis

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

Reading: Key Ideas and Details

Cite specific textual evidence to support analysis of science and technical texts, attending to the precise details of explanations or descriptions.

Reading: Key Ideas and Details

Determine the central ideas or conclusions of a text; trace the text’s explanation or depiction of a complex process, phenomenon, or concept; provide an accurate summary of the text.

Reading: Key Ideas and Details

Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks attending to special cases or exceptions defined in the text. 

Reading: Craft and Structure

Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 9–10 texts and topics.

Reading: Craft and Structure

Analyze the structure of the relationships among concepts in a text, including relationships among key terms (e.g., force, friction, reaction force, energy). 

Reading: Craft and Structure

Analyze the author’s purpose in providing an explanation, describing a procedure, or discussing an experiment in a text, defining the question the author seeks to address.

Reading: Integration of Knowledge and Ideas

Translate quantitative or technical information expressed in words in a text into visual form (e.g., a table or chart) and translate information expressed visually or mathematically (e.g., in an equation) into words.

Reading: Integration of Knowledge and Ideas

Compare and contrast findings presented in a text to those from other sources (including their own experiments), noting when the findings support or contradict previous explanations or accounts.

Reading: Range of Reading and Level of Text Complexity

By the end of grade 10, read and comprehend science/technical texts in the grades 9–10 text complexity band independently and proficiently

Writing: Production and Distribution of Writing

Produce clear and coherent writing in which the development, organization, and style are appropriate to task, purpose, and audience.

Writing: Research to Build and Present Knowledge

Gather relevant information from multiple authoritative print and digital sources, using advanced searches effectively; assess the usefulness of each source in answering the research question; integrate information into the text selectively to maintain the flow of ideas, avoiding plagiarism and following a standard format for citation.

Writing: Research to Build and Present Knowledge

Draw evidence from informational texts to support analysis, reflection, and research.

Writing: Range of Writing

Write routinely over extended time frames (time for reflection and revision) and shorter time frames (a single sitting or a day or two) for a range of discipline-specific tasks, purposes, and audiences.

Writing: Research to Build and Present Knowledge

Conduct short as well as more sustained research projects to answer a question (including a self-generated question) or solve a problem; narrow or broaden the inquiry when appropriate; synthesize multiple sources on the subject, demonstrating understanding of the subject under investigation.