Class Outline 

1. How do scientists work together to solve problems? 

• Science and Engineering Process Skills (ongoing throughout the year)

2. Chemical Reactions and Matter: How can we make something new that was not there before?

Phenomenon: Bath Bomb

Structure and Properties of Matter

• Substances are made from different types of atoms, which combine with one another in various ways.

• Atoms form molecules that range in size from two to thousands of atoms.

• Solids may be formed from molecules, or they may be extended structures with repeating subunits (e.g., crystals).

• Each pure substance has characteristic physical and chemical properties (for any bulk quantity under given conditions) that can be used to identify it.

Chemical Reactions

• Substances react chemically in characteristic ways. In a chemical process, the atoms that make up the original substances are regrouped into different molecules, and these new substances have different properties from those of the reactants.

• The total number of each type of atom is conserved, and thus the mass does not change.

Information Processing

• Each sense receptor responds to different inputs (electromagnetic, mechanical, chemical), transmitting them as signals that travel along nerve cells to the brain. The signals are then processed in the brain, resulting in immediate behaviors or memories.

MS-PS1-1 Develop models to describe the atomic composition of simple molecules and extended structures.

MS-PS1-2 Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred. 

MS-PS1-5 Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved.

MS-LS1-8 Gather and synthesize information that sensory receptors respond to stimuli by sending messages to the brain for immediate behavior or storage as memories.

3. Chemical Reactions and Energy: How can we use chemical reactions to design a solution to a problem? 

Chemical Reactions  

• Some chemical reactions release energy, while others store energy. 

Developing Possible Solutions  

• Models of all kinds are important for testing solutions.

• A solution needs to be tested and then modified on the basis of the test results in order to improve it. 

• There are systematic processes for evaluating solutions with respect to how well they meet the criteria and constraints of a problem.

• Sometimes parts of different solutions can be combined to create a solution that is better than any of its predecessors.

Optimizing the Design Solution  

• Although one design may not perform the best across all tests, identifying the characteristics of the design that performed the best in each test can provide useful information for the redesign process—that is, some of the characteristics may be incorporated into the new design.  

• The iterative process of testing the most promising solutions and modifying what is proposed on the basis of the test results leads to greater refinement and ultimately to an optimal solution. 

MS-PS1-6 Undertake a design project to construct, test, and modify a device that either releases or absorbs thermal energy by chemical processes.

MS-ETS1-2 Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.

MS-ETS1-3 Analyze data from tests to determine similarities and differences among several design solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.

MS-ETS1-4 Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.

4. Metabolic Reactions: How do things inside our body work together to make us feel the way we do?

Structure and Function

• In multicellular organisms, the body is a system of multiple interacting subsystems. These subsystems are groups of cells that work together to form tissues and organs that are specialized for particular body functions.

Growth and Development of Organisms

• The growth of an animal is controlled by genetic factors,* food intake, and interactions with other organisms, and each species has a typical adult size range.

Organization for Matter and Energy Flow in Organisms 

• Within individual organisms, food moves through a series of chemical reactions in which it is broken down and rearranged to form new molecules, to support growth, or to release energy. 

Energy in Processes and Everyday Life

• Cellular respiration in plants and* animals involves chemical reactions with oxygen that release stored energy. In these processes, complex molecules containing carbon react with oxygen to produce carbon dioxide and other materials. 

MS-LS1-3 Use argument supported by evidence for how the body is a system of interacting subsystems composed of groups of cells.

MS-LS1-5 Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms.

MS-LS1-7 Develop a model to describe how food is rearranged through chemical reactions forming new molecules that support growth and/or release energy as this matter moves through an organism.

MS-PS1-1 Develop models to describe the atomic composition of simple molecules and extended structures.

MS-PS1-2 Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.

5. Matter Cycling and Photosynthesis: Where does food come from and where does it go next?

Phenomena: Maple Syrup and Maple Sap

Organization for Matter and Energy Flow in Organisms

• Plants, algae (including phytoplankton), and many microorganisms use the energy from light to make sugars (food) from carbon dioxide from the atmosphere and water through the process of photosynthesis, which also releases oxygen. These sugars can be used immediately or stored for growth or later use.

Cycle of Matter and Energy Transfer in Ecosystems

• Food webs are models that demonstrate how matter and energy is transferred between producers, consumers, and decomposers as the three groups interact within an ecosystem. 

• Transfers of matter into and out of the physical environment occur at every level. Decomposers recycle nutrients from dead plant or animal matter back to the soil in terrestrial environments or to the water in aquatic environments. 

• The atoms that make up the organisms in an ecosystem are cycled repeatedly between the living and nonliving parts of the ecosystem.

Structure and Properties of Matter

• Each pure substance has characteristic physical and chemical properties (for any bulk quantity under given conditions) that can be used to identify it.

Chemical Reactions

• Substances react chemically in characteristic ways. In a chemical process, the atoms that make up the original substances are regrouped into different molecules, and these new substances have different properties from those of the reactants.

Energy in Chemical Processes and Everyday Life

• The chemical reaction by which plants produce complex food molecules (sugars) requires an energy input (i.e., from sunlight) to occur. In this reaction, carbon dioxide and water combine to form carbon-based organic molecules and release oxygen. (secondary)

MS-LS1-6 Construct a scientific explanation based on evidence for the role of photosynthesis in the cycling of matter and flow of energy into and out of organisms.

MS-LS1-2 Develop and use a model to describe the function of a cell as a whole and ways parts of cells contribute to the function.

MS-LS2-3 Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem.

MS-PS1-3 Gather and make sense of information to describe that synthetic materials come from natural resources and impact society.

6. Genetics: Why are living things different from one another?

Phenomena: Muscular Cattle and Environmental Factors that Influence Genetic Variation

• Genetic factors as well as local conditions affect the growth of the adult plant.

• Organisms reproduce, either sexually or asexually, and transfer their genetic information to their offspring.

• Genes are located in the chromosomes of cells, with each chromosome pair containing two variants of each of many distinct genes. Each distinct gene chiefly controls the production of specific proteins, which in turn affects the traits of the individual. Changes (mutations) to genes can result in changes to proteins, which can affect the structures and functions of the organism and thereby change traits.

• Variations of inherited traits between parent and offspring arise from genetic differences that result from the sub-set of chromosomes (and therefore genes) inherited.

• In addition to variations that arise from sexual reproduction, genetic information can be altered because of mutations. Though rare, mutations may result in changes to the structure and function of proteins. Some changes are beneficial, others are harmful, and some are neutral to the organism.

• In sexually reproducing organisms, each parent contributes half of the genes acquired (at random) by the offspring. Individuals have two of each chromosome and hence two alleles of each gene, one acquired from each parent. These versions may be identical or may differ from each other.

• In artificial selection, humans have the capacity to influence certain characteristics of organisms by selective breeding. One can choose desired parental traits determined by genes, which are then passed on to offspring.

• Plants reproduce in a variety of ways, sometimes depending on animal behavior and specialized features for reproduction.

• Within cells, special structures are responsible for particular functions, and the cell membrane forms the boundary that controls what enters and leaves the cell.

Inheritance and Variation

MS-LS3-1 Analyze and interpret data to provide evidence that plants and animals have traits inherited from parents and that variation of these traits exists in a group of similar organisms. 

MS-LS3-2  Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.

Evolution - Unity and Diversity

MS-LS4-5 Gather and synthesize information about technologies that have changed the way humans influence the inheritance of desired traits in organisms.

Molecules to Organisms

MS-LS1-5 Construct a scientific explanation based on evidence for how environmental and genetic factors influence the growth of organisms. 

7. Natural Selection and Common Ancestry: How could things living today be connected to the things that lived long ago?

Phenomena: Connection Between Modern and Ancient Organisms

Growth and Development of Organisms:  

• Animals engage in characteristic behaviors that increase the odds of reproduction.

Evidence of Common Ancestry and Diversity:

• The collection of fossils and their placement in chronological order (e.g., through the location of the sedimentary layers in which they are found or through radioactive dating) is known as the fossil record. It documents the existence, diversity, extinction, and change of many life forms throughout the history of life on Earth. 

• Anatomical similarities and differences between various organisms living today, and between them and organisms in the fossil record, enable the reconstruction of evolutionary history and the inference of lines of evolutionary descent. 

• Comparison of the embryological development of different species also reveals similarities that show relationships not evident in the fully formed anatomy. 

• Natural selection leads to the predominance of certain traits in a population and the suppression of others.

• Adaptation by natural selection acting over generations is one important process by which species change over time in response to changes in environmental conditions. Traits that support successful survival and reproduction in the new environment become more common and those that do not become less common. Thus, the distribution of traits in a population changes.

Molecules to Organisms

MS-LS1-4 Use argument based on empirical evidence and scientific reasoning to support an explanation for how characteristic animal behaviors and specialized plant structures affect the probability of successful reproduction of animals and plants respectively.

Evolution - Unity and Diversity

MS-LS4-1 Analyze and interpret data for patterns in the fossil record that document the existence, diversity, extinction, and change of life forms throughout the history of life on Earth under the assumption that natural laws operate today as in the past.

MS-LS4-2  Apply scientific ideas to construct an explanation for the anatomical similarities and differences among modern organisms and between modern and fossil organisms to infer evolutionary relationships.

MS-LS4-3  Construct an argument with evidence that in a particular habitat, some organisms can survive well, some survive less well, and some cannot survive at all.

MS-LS4-4  Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment.

MS-LS4-6  Use mathematical representations to support explanations of how natural selection may lead to increases and decreases of specific traits in populations over time.

8. Comprehensive Health: 

Your 7th grade child will be involved in a science-based Reproductive and Social Health education program in the classroom. This program meets Colorado State Standards for Science, Comprehensive Health and Physical Education, and is in alignment with Colorado State laws HB13-1081 and HB1292.

This prioritized Health and Science education program uses the Colorado Department of Education grade level expectations and outcomes for 7th grade as follows:

1. Explain the structure, function and major parts of the human reproductive system

2. Describe the physical, social, and emotional changes that occur at puberty

3. Demonstrate interpersonal communication skills needed to discuss personal health problems to establish and maintain personal health and wellness

4. Comprehend concepts and identify strategies to prevent the transmission of disease

You may examine all instructional materials at the Division of Equity in Learning Office by appointment with the Health Education TOSA. If you have questions, please contact Shelia Siegert, Assistant to the Director, Teaching & Learning.