Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the last of four Science Objects in the Force and Motion SciPack. It provides a conceptual and real-world understanding of Newton’s Third Law of Motion, addressing common misconceptions associated with this law. Whenever one object exerts a force on another, an equal amount of force is exerted back on it. These equal and opposite forces are exerted simultaneously on the objects involved.
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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the first of four Science Objects in the Cell Structure and Function SciPack. It explores the difference between living and non-living things as it looks at the many different types of cells. All self-replicating life forms are composed of cells,-from single-celled bacteria to elephants, with their trillions of cells. Although a few giant cells, such as hens' eggs, can be seen with the naked eye, most cells are microscopic. Multi-celled organisms are composed of many tiny microscopic cells, as opposed to fewer larger cells. Surface area to volume ratio makes efficient food absorption and waste removal possible in cells.
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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the first of three Science Objects in the Flow of Matter and Energy in Ecosystems SciPack. It explores the structure of the biomass in an ecosystem and overall cycling of matter. However complex the workings of living organisms, they share with all other systems the same physical principles that describe the conservation and transformation of matter.

Ecosystems are a community of interdependent organisms and the chemical and physical factors making up the environment with which they interact. For every ecosystem on Earth there is a particular biomass (matter) distribution among organisms in its populations. While the specific biomass distribution in any given ecosystem is unique because of resource availability, there is a common overall biomass distribution pattern in all ecosystems. Greater biomass exists in populations that obtain matter from the physical environment than in populations that obtain matter from other living organisms. As matter flows through different levels of organization in living systems—cells, organs, organisms, communities—and between living systems and the physical environment, chemical elements are recombined in different ways. Matter is conserved through each change.

Learning Outcomes:

• Define an ecosystem and understand how it comprises an interdependent community of organisms along with their interactions with the chemical and physical components of the environment
• Categorize organisms in a community based on their sources of matter/biomass and nutrients as one of the following: producers, herbivores (primary consumers), carnivores (secondary consumers; tertiary or top-consumers),
• omnivores, and decomposers
• Predict the relative biomass for different levels in a biomass pyramid for a typical ecosystem
• Explain how matter is conserved in the interactions between consumers and producers, but that in a biomass pyramid there is less biomass at the consumer level compared to the producer level

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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the third of three Science Objects in the Flow of Matter and Energy in Ecosystems SciPack. It explores how energy flows through an ecosystem in one direction, from photosynthetic organisms to herbivores to omnivores and carnivores and decomposers. As the energy flows, less and less energy isavailable to support life.

Plants capture the sun's energy and use it to synthesize complex, energy-rich molecules (chiefly sugars) from molecules of carbon dioxide and water. Because plants and other photosynthetic organisms use energy from the sun and inorganic molecules from the environment to produce organic molecules needed for life, they are called producers. The organisms that consume the producers (called consumers) derive energy and materials from breaking down the producers’ molecules, use them to synthesize their own structures and then may be consumed by other organisms. Decomposers (organisms that break down dead producers and consumers and organic waste) obtain the energy they need to live from chemical bonds of the dead and waste-matter. The energy is transferred both to the decomposer (for growth and development) and to the ecosystem (as heat energy). Food webs and energy pyramids are models or representations that can be used to track the flow of energy in the ecosystem. Food webs detail the flow of energy through the populations in the ecosystems whereas the pyramid model quantifies the flow of energy through various levels in an ecosystem. Unlike matter, as energy flows through an ecosystem in one direction, from photosynthetic organisms to herbivores to omnivores and carnivores and decomposers, less and less energy becomes available to support life. This loss of useable energy occurs because each energy transfer results in the dissipation of some energy into the environment as heat. Continual input of energy from sunlight is necessary to keep ecosystems organized and functioning.

Learning Outcomes:

• Explain how a food web describes the flow of energy within an ecosystem
• Explain the role that the amount of sunlight available to an ecosystem plays on defining the size and types of populations within an ecosystem
• Use the characteristics of energy transfer (from one population to another) to explain the structure of an energy pyramid for organisms living in a community
• Explain why, if energy is conserved in the interaction of consumers and producers, there is less energy at the consumer level compared to the producer level in an energy pyramid
• Explain why a vegetarian diet for humans requires less energy to produce the food needed than a diet that includes meat and fish does
• Compare the flow of matter with the flow of energy among organisms and between organisms and their environment in an ecosystem

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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the first of three Science Objects in the Heredity and Variation SciPack. It explores the historical perspective and experiments of Mendel.

Sexual reproduction results in the continuity of species accompanied with a great deal of variation in physical traits. One familiar observation is that offspring are very much like their parents but still show some variation— differing somewhat from their parents and from one another. People have long been curious about heredity, using even the most primitive understanding of inheritance to cultivate desirable traits in domesticated species. In the 1800s, Gregor Mendel took his observations of heredity and variation to new heights through carefully designed and executed breeding experiments that generated repeatable inheritance patterns. Mendel developed a model for explaining the patterns he observed, describing discrete units or “particles,” which both segregate and assort independently of one another during inheritance. This model offered a foundational explanation for how variation is generated through sexual reproduction. Although Mendel’s model over-simplified how traits are inherited and expressed, it set the stage for the discoveries of chromosomes and genes from which contemporary genetics grew.

Learning Outcomes:

• Explain how domestication of plants and animals produced an early understanding of inheritance.
• Use Mendel’s model to explain patterns of inheritance represented in graphic form (for example, data tables, histograms, etc.).
• Identify the conditions required for an inheritance pattern to be explained correctly by Mendel’s model.
• Use data representing patterns of inheritance to support the idea that some observable traits are defined by discrete units of inheritance that segregate and assort independently of one another during inheritance.

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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the third of four Science Objects in the Earth, Sun, and Moon SciPack. It provides an understanding of the moon’s orbit around Earth and the phases of the moon as experienced from Earth’s surface. The Moon orbits Earth approximately once per month, causing the pattern of moon phases. Although half of the Moon’s surface is always illuminated by the Sun and half is always shaded, the portion of the illuminated surface that we see changes as the Moon orbits Earth.
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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the second of four Science Objects in the Earth, Sun, and Moon SciPack. It provides an understanding of how we know that Earth moves in a nearly circular orbit around the Sun once per year, so that we see different constellations at different times of the year. Earth rotates on its axis once per day, making it appear as though the Sun, the Moon, and the stars revolve around Earth each day. Evidence however, demonstrates that it is in fact, Earth that rotates on its axis as it orbits the Sun, just as other planets in our solar system.
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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the first of four Science Objects in the Force and Motion SciPack. It provides an understanding of how changes in position and motion can affect the way objects move, focusing on constant motion (where the direction and speed remain the same) and acceleration (a change in motion due to a change in an object’s direction or speed). The position of an object must be described relative to some other object while the motion of an object can be described by its direction and speed. Velocity is a measure of both an object’s speed and its direction (and can be described by vectors).
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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the second of four Science Objects in the Interdependence of Life SciPack. It explores species relationships.

All organisms, both land-based and aquatic, are interrelated by their need for resources. One example of a network of interconnections is called a food web; it is a model of the interdependence among the organisms in populations of different species. Predator-prey and parasitic relationships are examples of interspecies relationships, interdependence that occurs among organisms in different species in a food web.

Interspecies relationships can be categorized as positive, negative, or neutral for the fitness of the individuals and their populations who are involved. A change in the population of one species can affect the population of another species. Intra-species relationships, or interdependence among organisms of the same species, can also affect a population.

Learning Outcomes:

• Given the specific nature of an interspecies relationship, categorize the relationship between two interrelated populations as positive, negative or neutral for each population.
• Given a description of a change to one population depicted in a food web, predict changes that might occur in the size and rate of growth for other populations depicted in the food web.
• Given a line graph displaying changes in population sizes and rates of growth for a number of populations in a community, along with a description of the trophic relationships among populations, generate plausible hypotheses about causes of the changes depicted in the graph.

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Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach. This Science Object is the second of three Science Objects in the Flow of Matter and Energy in Ecosystems SciPack. It explores how the cycling of carbon and other nutrients from non-living to living components and back is one of the most important of ecosystem functions and is representative of the cycling of other elements.

All matter that comprises organic molecules, including hydrogen, oxygen, nitrogen, phosphorous and others are transferred cyclically among living organisms and their non-living environment. The cycling of elements from non-living to living components and back is one of the most important ecosystem characteristics. For example, carbon, an essential element in organic molecules, is conserved as it is transferred from inorganic carbon in an ecosystem to organic molecules in living organisms of the ecosystem and back as inorganic carbon to the environment. The carbon cycle, in the following description, serves as an example of one of the essential biogeochemical cycles.

Learning Outcomes:

• Trace the path of a carbon atom from the atmosphere through a biomass pyramid and ultimately back to the atmosphere
• Describe how photosynthesis and consumer respiration affect the flow of carbon through an ecosystem
• Predict the biological effects of increasing levels of atmospheric carbon due to the massive combustion of fossil fuels
• Identify the process that emits carbon to the atmosphere from producers, consumers and decomposers

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