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Cell Division and Differentiation: Variation and Specialization of Cells Science Object
Science Object
Cell Division and Differentiation: Variation and Specialization of Cells
Grade Level: Elementary School, High School, Middle School
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 Cell Division and Differentiation SciPack. It explores the processes that take place within cells that allow for selective gene expression, which leads to the specialization and variation of cells in organisms. Cell functions are turned...  [view full summary]

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 Cell Division and Differentiation SciPack. It explores the processes that take place within cells that allow for selective gene expression, which leads to the specialization and variation of cells in organisms.

Cell functions are turned on and off by regulatory genes, through changes in the activity of the functions performed by proteins. Although cells in a multi–celled organism begin alike, having essentially identical genetic instructions, selective expression of individual genes (cells are regulated) causes the unspecialized embryonic stem cells to become very different (cells can differentiate). The embryonic stem cells become increasingly more specialized, differentiating into a variety of cell types. Selective expression results when different parts of the genetic instructions are used in different types of cells, influenced by the cell's environment and past history.

The work of the cell is carried out by the many different types of molecules it assembles, mostly proteins. In specialized cells, other protein molecules may carry oxygen, effect contraction, respond to outside stimuli, or provide material for other body structures. In still other cells, assembled molecules may be exported to serve as hormones, antibodies, or digestive enzymes.

Learning Outcomes:
  • Explain the role of regulatory genes and how they function.
  • Explain how it is possible for different types of cells, such as bone cells and liver cells, to have identical genetic instructions and function differently.
  • Describe the role of embryonic stem cells in the development and growth of complex organisms.
  • Interpret data presented in graphs and charts from experiments addressing the role that protein-related variables (such as hormones, antibodies and digestive enzymes) play in the regulation of a complex organism’s life processes.

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Earth, Sun, and Moon: Earth's Seasons Science Object
Science Object
Earth, Sun, and Moon: Earth's Seasons
Grade Level: Elementary School, Middle School
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, co-developed between NASA and NSTA, is the last of four Science Objects in the Earth, Sun, and Moon SciPack. It provides an understanding of why we have different seasons on Earth and why seasons vary from one location on Earth and another. The Sun is the major source of energy for...  [view full summary]
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, co-developed between NASA and NSTA, is the last of four Science Objects in the Earth, Sun, and Moon SciPack. It provides an understanding of why we have different seasons on Earth and why seasons vary from one location on Earth and another. The Sun is the major source of energy for phenomena on Earth’s surface. The seasons are caused by the tilt of Earth’s axis with respect to the plane of its orbit around the Sun. Because the angle and direction of tilt does not change as Earth orbits the Sun, during half of the year the north polar region tilts toward the Sun, resulting in increased heating (summer) and away from the Sun during the other half of the year, resulting in cooling (winter). The seasons are reversed in the Southern Hemisphere.
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Electric and Magnetic Forces: Electrostatics and Current Electricity Science Object
Science Object
Electric and Magnetic Forces: Electrostatics and Current Electricity
Grade Level: Elementary School, Middle School
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 Electric and Magnetic Forces SciPack. It explores the ability of electrons to flow, producing an electric current. Negative charges, being associated with electrons on the outer edges of atoms, are far more mobile in materials than...  [view full summary]
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 Electric and Magnetic Forces SciPack. It explores the ability of electrons to flow, producing an electric current. Negative charges, being associated with electrons on the outer edges of atoms, are far more mobile in materials than positive charges located in the nucleus at the center of an atom. In some materials, such as metals, electrons flow easily, whereas in insulating materials such as glass they can hardly flow at all. At very low temperatures, some materials become superconductors and offer no resistance to the flow of current. In between these extremes, semi-conducting materials differ greatly in how well they conduct, depending on their exact composition. Electric currents occur when charges move through conductors. Batteries and other devices store electrical energy by separating and concentrating charges. Electrical circuits provide a means of transferring electrical energy into other forms of energy such as heat, light, and sound.
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Electric and Magnetic Forces: Electromagnetism Science Object
Science Object
Electric and Magnetic Forces: Electromagnetism
Grade Level: Elementary School, Middle School
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 three Science Objects in the Electric and Magnetic Forces SciPack. It explores magnets, magnetic forces, and the relationship between magnetic and electric forces. Magnetic and electric forces are closely related and can be thought of as different aspects of a single...  [view full summary]
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 three Science Objects in the Electric and Magnetic Forces SciPack. It explores magnets, magnetic forces, and the relationship between magnetic and electric forces. Magnetic and electric forces are closely related and can be thought of as different aspects of a single electromagnetic force. Both electric and magnetic forces are thought of as acting by means of fields: an electric charge has an electric field in the space around it that affects other charges, and a magnet has a magnetic field around it that affects other magnets. Moving electric charges produce magnetic fields and are affected by magnetic fields. More generally, a changing electric field induces a magnetic field, and vice versa. This interaction is the basis of many natural phenomena. For example, electric currents circulating in the earth's core give the earth an extensive magnetic field, which we detect from the orientation of our compass needles. The interplay of electric and magnetic fields is also the basis for electric motors, generators, and many other modern technologies.
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Energy: Different Kinds of Energy Science Object
Science Object
Energy: Different Kinds of Energy
Grade Level: Elementary School, High School, Middle School
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 Energy SciPack. It provides a conceptual and real-world understanding of the different types of energy. Energy can appear in many different forms, however all forms of energy can be broadly classified as one or a combination of two kinds:...  [view full summary]
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 Energy SciPack. It provides a conceptual and real-world understanding of the different types of energy. Energy can appear in many different forms, however all forms of energy can be broadly classified as one or a combination of two kinds: kinetic energy, which is the energy of motion; and potential energy, which depends on the relative position or shape of an object. Other kinds of energy include gravitational energy (the separation of mutually attracting masses), thermal energy (the disorderly motion of atoms or molecules), and chemical energy (the arrangement of atoms).
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Energy: Energy Transformations Science Object
Science Object
Energy: Energy Transformations
Grade Level: Elementary School, High School, Middle School
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 Energy SciPack. It provides a conceptual and real-world understanding of how energy is transferred, from object to object and from one form of energy to another. Although the various forms of energy appear different, each can be measured...  [view full summary]
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 Energy SciPack. It provides a conceptual and real-world understanding of how energy is transferred, from object to object and from one form of energy to another. Although the various forms of energy appear different, each can be measured in a closed system. This makes it possible to keep track of how much of one form of energy is converted into another form. Most of what goes on in the universe—from exploding stars and biological growth to the operation of machines and the motion of people—involves some form of energy being transformed into another form. The law of conservation of energy states that whenever the amount of energy in one place (or form) decreases, the amount of energy in other places (or forms) increases by the same amount.
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Energy: Thermal Energy, Heat, and Temperature Science Object
Science Object
Energy: Thermal Energy, Heat, and Temperature
Grade Level: Elementary School, High School, Middle School
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 Energy SciPack. It provides a conceptual and real-world understanding of the relationship between thermal energy, heat, and temperature. The thermal energy of a material consists of the disordered motion of its atoms or molecules. Thermal...  [view full summary]
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 Energy SciPack. It provides a conceptual and real-world understanding of the relationship between thermal energy, heat, and temperature. The thermal energy of a material consists of the disordered motion of its atoms or molecules. Thermal energy can be transferred through materials or from one material to another by conduction (the collisions of atoms), or across space by radiation. If the material is fluid, convection currents aid the transfer of thermal energy (convection). When thermal energy is transferred it is called heat. Temperature is a measure of the average kinetic energy of atoms and molecules in a material.
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Energy: Useful and Not So Useful Energy Science Object
Science Object
Energy: Useful and Not So Useful Energy
Grade Level: Elementary School, High School, Middle School
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 fourth of four Science Objects in the Energy SciPack. It provides a conceptual and real-world understanding of why energy in some forms can easily be used but in other forms is difficult to use. Energy transformations usually produce some heat, which is transferred to cooler...  [view full summary]
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 fourth of four Science Objects in the Energy SciPack. It provides a conceptual and real-world understanding of why energy in some forms can easily be used but in other forms is difficult to use. Energy transformations usually produce some heat, which is transferred to cooler places or objects in the surrounding area via radiation or conduction. In such interactions the number of atoms or molecules is very large and statistics dictate that they will end up with less order than that the initial state. Although just as much total energy remains, it is more widely distributed or spread out which means less can be done with it. This is because useful transfer of energy can be accomplished only when energy is concentrated (such as in falling water, in high-energy molecules in fuels and food, or in radiation from sources such as the intensely hot sun).
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Earth, Sun, and Moon: General Characteristics of Earth Science Object
Science Object
Earth, Sun, and Moon: General Characteristics of Earth
Grade Level: Elementary School, High School, Middle School
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, co-developed between NASA and NSTA, is the first of four Science Objects in the Earth, Sun, and Moon SciPack. It provides an understanding of how the different spheres (atmosphere, lithosphere, and hydrosphere) of Earth interact and why each plays an important role in making Earth...  [view full summary]
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, co-developed between NASA and NSTA, is the first of four Science Objects in the Earth, Sun, and Moon SciPack. It provides an understanding of how the different spheres (atmosphere, lithosphere, and hydrosphere) of Earth interact and why each plays an important role in making Earth the only planet with the conditions necessary for life. Earth is approximately spherical in shape like all planets and stars. Earth is composed mostly of rock. Three-fourths of its surface is covered by a relatively thin layer of water (some of it frozen), and the entire planet is surrounded by a relatively thin blanket of air.
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Earth, Sun, and Moon: Our Moving Earth Science Object
Science Object
Earth, Sun, and Moon: Our Moving Earth
Grade Level: Elementary School, Middle School
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, co-developed between NASA and NSTA, 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...  [view full summary]
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, co-developed between NASA and NSTA, 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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