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Coral Reef Ecosystems: Ecosystems in Crisis
 Science Object
Science Object
Coral Reef Ecosystems: Ecosystems in Crisis
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 NOAA and NSTA, is the fourth of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the natural and human causes of ecosystem stress. Human beings live near coral ecosystems and use them in a variety of ways. Increasing amounts of stress is brought...  [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 NOAA and NSTA, is the fourth of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the natural and human causes of ecosystem stress. Human beings live near coral ecosystems and use them in a variety of ways. Increasing amounts of stress is brought on these ecosystems as humans continue to modify the surrounding environment as a result of population growth, technology, and consumption. Human destruction of habitats through direct harvesting, pollution, atmospheric changes, and other factors is threatening the stability and overall health of many coral reefs. Human activities may also exacerbate the impact of natural disturbances on coral reefs or compromise the ability of the reef to recover from events such as hurricanes, tsunamis, or disease.
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Coral Reef Ecosystems: Interdependence Science Object
Science Object
Coral Reef Ecosystems: Interdependence
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 NOAA and NSTA, is the third of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the interdependent relationships between species in the coral reef ecosystem. All populations in the reef ecosystem are a part of and depend on a global food web...  [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 NOAA and NSTA, is the third of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the interdependent relationships between species in the coral reef ecosystem. All populations in the reef ecosystem are a part of and depend on a global food web (a connected set of food chains) through which energy flows in one direction, from the sun into organism and eventually dissipating into the environment as heat. This food web includes ocean plants, the animals that feed on them, and the animals that feed on those animals. Energy is transferred between organisms and their environment along the way. Energy concentration diminishes at each step. The cycles of life continue indefinitely because organisms decompose after death and return food materials to the environment.
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Chemical Reactions: A World of Reactions Science Object
Science Object
Chemical Reactions: A World of Reactions
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 first of four Science Objects in the Chemical Reactions SciPack. It explains that chemical reactions occur all around us, for example in health care, cooking, cosmetics, and automobiles. An enormous variety of biological, chemical, and physical phenomena can be explained by changes...  [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 Chemical Reactions SciPack. It explains that chemical reactions occur all around us, for example in health care, cooking, cosmetics, and automobiles. An enormous variety of biological, chemical, and physical phenomena can be explained by changes in the arrangement and motion of atoms and molecules. An atom's electron configuration, particularly the outermost electrons, determines how the atom can interact with other atoms. Atoms form bonds to other atoms by transferring or sharing electrons. Carbon atoms can bond to one another in chains, rings, and branching networks to form a variety of structures, and complex chemical reactions involving these molecules take place constantly in every cell in living objects.
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Chemical Reactions: Rates of Chemical Reactions Science Object
Science Object
Chemical Reactions: Rates of Chemical Reactions
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 third of four Science Objects in the Chemical Reactions SciPack. It demonstrates how chemical reactions can take place in time periods ranging from the few femto-seconds (10-15 seconds) required for an atom to move a fraction of a chemical bond distance to geologic time scales...  [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 Chemical Reactions SciPack. It demonstrates how chemical reactions can take place in time periods ranging from the few femto-seconds (10-15 seconds) required for an atom to move a fraction of a chemical bond distance to geologic time scales of billions of years. The rate of reactions among atoms and molecules depends on how often they encounter one another, which is affected by the concentration, pressure (for gases), and temperature of the reacting substances. The configuration of atoms in a molecule determines the molecule's properties. Shapes are particularly important in determining how large molecules interact with others. Some atoms and molecules called catalysts are highly effective in accelerating chemical reactions. Chemical reactions in living systems are catalyzed by protein molecules called enzymes.
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Chemical Reactions: Categorizing Chemical Reactions Science Object
Science Object
Chemical Reactions: Categorizing Chemical Reactions
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 four Science Objects in the Chemical Reactions SciPack. It provides an understanding of the idea that a large number of important reactions involve the transfer of either electrons (oxidation/reduction reactions) or hydrogen ions (acid/base reactions) between reacting...  [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 Chemical Reactions SciPack. It provides an understanding of the idea that a large number of important reactions involve the transfer of either electrons (oxidation/reduction reactions) or hydrogen ions (acid/base reactions) between reacting ions, molecules, or atoms. In other reactions, chemical bonds are broken by heat or light to form very reactive radicals with electrons ready to form new bonds. Reactions involving these radicals control many processes such as the presence of ozone and greenhouse gases in the atmosphere, burning and processing of fossil fuels, the formation of polymers, and explosions.
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Coral Reef Ecosystems: The Abiotic Setting Science Object
Science Object
Coral Reef Ecosystems: The Abiotic Setting
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 NOAA and NSTA, is the second of four Science Objects in the Coral Reef Ecosystems SciPack. It investigates the abiotic characteristics that affect the coral reef ecosystem. The number and kinds of organisms found along each reef depend on the physical conditions...  [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 NOAA and NSTA, is the second of four Science Objects in the Coral Reef Ecosystems SciPack. It investigates the abiotic characteristics that affect the coral reef ecosystem. The number and kinds of organisms found along each reef depend on the physical conditions of the environment and resources available, including food, light, water quality, temperature, and other organisms living in the reef. If conditions change significantly due to changes in climate, loss of food sources, excessive predation, or loss of habitat, the health and stability of the ecosystem will be affected. Like many complex systems, coral ecosystems tend to have cyclic fluctuations around a state of rough equilibrium. In the long run, if conditions remain reasonably constant a coral ecosystem can be stable for hundreds of years.
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Cell Division and Differentiation: Continuity of Life Science Object
Science Object
Cell Division and Differentiation: Continuity of Life
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 three Science Objects in the Cell Division and Differentiation SciPack. It discusses the basics of cell division, the cell cycle, and how cells continue from one generation to the next. Cells carry on the many functions needed to sustain life, including cell growth...  [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 three Science Objects in the Cell Division and Differentiation SciPack. It discusses the basics of cell division, the cell cycle, and how cells continue from one generation to the next.

Cells carry on the many functions needed to sustain life, including cell growth and development. The genetic information encoded in DNA molecules provides instructions for assembling protein molecules, which are both necessary for producing more cells and performing other cellular functions. Before a cell divides, the instructions are duplicated so that each of the two new cells gets all the necessary information for carrying on. Complex interactions among the different kinds of molecules in the cell cause distinct cycles of activities, including cell growth and division. Cell activity can also be affected by molecules from other parts of the organism, or even other organisms. Cells in multi–cellular organisms repeatedly divide to make more cells for growth and repair. Without cell division the surface area to volume ratio that constrains the size of single cells would limit an organism’s growth. Cell division in single–cell organisms makes asexual reproduction possible. Changes in DNA (mutations) occur spontaneously at low rates. Some of these changes make no difference to the organism, whereas others can change cells and organisms. In multi–cellular organisms, uncontrolled cell division, called cancer, can be caused by gene mutation. Exposure of cells to certain chemicals or radiation increases mutations and thus increases the chance of cancer.

Learning Outcomes:
  • Describe the cellular events related to genetic material that must occur for cell division leading to growth or repair in multicellular organisms.
  • Interpret the results of experimental variables, both internal and external to the cell, affecting cellular growth and division displayed within an experiment’s graphs or data charts.
  • Compare and contrast normal, healthy cell division and cancer.
  • Explain at the cellular level how recommendations for cancer prevention (i.e. smoking cessation) might influence and affect incidents of cancer.

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Cells and Chemical Reactions: Reaction Rates in Cells Science Object
Science Object
Cells and Chemical Reactions: Reaction Rates in 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 last of four Science Objects in the Cells and Chemical Reactions SciPack. It investigates how the reaction rates in cells can be affected by temperature, pH, hydration levels, and enzymes.

Chemical reaction rates are affected by the conditions in which they occur (or...  [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 four Science Objects in the Cells and Chemical Reactions SciPack. It investigates how the reaction rates in cells can be affected by temperature, pH, hydration levels, and enzymes.

Chemical reaction rates are affected by the conditions in which they occur (or cannot occur). Most cells must function within a narrow range of temperature and acidity because they are part of a living system. At very low temperatures, reaction rates are too slow. High temperatures and/or extremes of acidity can irreversibly change the structure of most protein molecules. Even small changes in acidity can alter the molecules and how they interact. Hydration levels also affect chemical reactions in cells; dehydrated cells lack the solvent and substrate or substrate structure needed for chemical reactions to proceed. Both decomposition and synthesis of molecules (involving energy transfer) are made possible in cells by a large set of protein catalysts, called enzymes. Without enzymes to catalyze the chemical reactions necessary for life, the conditions (including temperature) inside of cells would slow chemical reaction rates below what is necessary to stay alive. Like other protein reactions, the effectiveness of enzymes reactions is affected by temperature and acidity.
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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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Coral Reef Ecosystems: The Living Reef Science Object
Science Object
Coral Reef Ecosystems: The Living Reef
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 NOAA and NSTA, is the first of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the unique and diverse ecosystem of the coral reef. Coral reefs are very complex systems that create one of the largest structures on Earth of biological origins....  [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 NOAA and NSTA, is the first of four Science Objects in the Coral Reef Ecosystems SciPack. It explores the unique and diverse ecosystem of the coral reef. Coral reefs are very complex systems that create one of the largest structures on Earth of biological origins. Thousands of coral species exist in oceans worldwide. Reef-building corals remain on the same spot of the sea floor through their entire lives and have developed reproductive, feeding, and social behaviors suited to their situation. As they grow, reefs provide structural habitats for hundreds to thousands of different organisms.
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