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Cells and Chemical Reactions: Cellular Respiration Science Object
Science Object
Cells and Chemical Reactions: Cellular Respiration
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 Cells and Chemical Reactions SciPack. It explores the process of cellular respiration in chemical reactions involved.

Non-photosynthetic organisms obtain the energy necessary for cell growth and maintenance by decomposing large...  [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 Cells and Chemical Reactions SciPack. It explores the process of cellular respiration in chemical reactions involved.

Non-photosynthetic organisms obtain the energy necessary for cell growth and maintenance by decomposing large molecules into smaller molecules that have lower energy levels stored in their chemical bonds (thus, releasing some energy from bonds so that it can be used to do cellular work). These smaller molecules can enter or exit the cell to be synthesized into larger complex molecules necessary for growth and maintenance of the organism. Organisms unable to photosynthesize, such as animals and fungi, must take matter into their cells to provide the building blocks (chemical constituents) and energy needed for metabolism (both synthesis and decomposition processes). The matter and energy that is stored in the structures that are synthesized by photosynthetic organisms (for example, the stems, roots and leaves of plants) can be consumed and used by other organisms as an essential source of this matter and energy.

The chemical bonds in the molecules that are synthesized through photosynthesis and other synthesis processes contain energy that is needed by all cells (including plant cells). The energy stored in chemical bonds of the matter taken into the cells can be released and transferred into a form available for cellular work. This occurs when the bonds are broken through decomposition reactions and new compounds with lower energy bonds are formed. Cells capture some of the energy that is released during decomposition and usually store this energy temporarily in the phosphate bonds of a small high-energy compound called ATP. The energy stored in the bonds of ATP is then readily available for use by the cell for synthesis and other cellular work.
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Cells and Chemical Reactions: Photosynthesis Science Object
Science Object
Cells and Chemical Reactions: Photosynthesis
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 Cells and Chemical Reactions SciPack. It investigates the process of photosynthesis and the chemical reactions that take place in plant cells.

Photosynthesis involves unique synthesis chemical reactions in which energy from the...  [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 Cells and Chemical Reactions SciPack. It investigates the process of photosynthesis and the chemical reactions that take place in plant cells.

Photosynthesis involves unique synthesis chemical reactions in which energy from the sun is transferred into energy in the chemical bonds that are formed when smaller molecules are combined to synthesize complex molecules. For nearly every living organism on Earth, the energy required by its cells originally comes from the sun and the only way to transfer light energy into living systems is through photosynthesis. Only those organisms with chlorophyll, such as plants, can capture energy by absorbing light and using it to form strong (covalent) chemical bonds between atoms of carbon-containing (organic) molecules through photosynthesis. Plants have chlorophyll contained in chloroplasts (the site of photosynthesis) where energy rich organic compounds are synthesized for use by the plant as a source of matter and energy necessary for life. This process of photosynthesis provides a vital connection between the sun and the energy needs of nearly all living systems, and also releases oxygen to the environment.

The simple carbohydrates produced during photosynthesis can be decomposed immediately to supply matter and energy needed for metabolic processes by plants or other photosynthesizing organisms. In addition, the energy from the decomposition can be used to build other complex carbon-based molecules that help the plant grow and function (including proteins, lipids and more complex carbohydrates).
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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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Ocean's Effect on Weather and Climate: Global Climate Patterns
 Science Object
Science Object
Ocean's Effect on Weather and Climate: Global Climate Patterns
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 NOAA and NSTA, is the first of four Science Objects in the Ocean’s Effect on Weather and Climate SciPack. It explores global weather and climate patterns, focusing on why different conditions exist in specific areas. Earth’s weather patterns, which consist of 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 NOAA and NSTA, is the first of four Science Objects in the Ocean’s Effect on Weather and Climate SciPack. It explores global weather and climate patterns, focusing on why different conditions exist in specific areas. Earth’s weather patterns, which consist of different conditions of temperature, precipitation, humidity, wind, air pressure, and other atmospheric phenomena, result in various climate zones across the globe. Weather and climate are the result of the transfer of energy from the Sun at and near the surface of Earth. Solar radiation heats land masses, oceans, and air differently, resulting in the constant transfer of energy as energy is “balanced” across the globe. Transfer of thermal energy at the boundaries between the atmosphere, land masses, and the oceans—influenced by dynamic processes such as cloud cover and relatively static conditions such as the position of mountain ranges and oceans—results in layers of different temperatures and densities in both the ocean and atmosphere. The action of gravitational force on regions of different densities causes them to rise or fall, forming convection currents (cells). This circulation, influenced by the rotation of the earth, produces winds and ocean currents.
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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: Basics of Metabolism Science Object
Science Object
Cells and Chemical Reactions: Basics of Metabolism
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 Cells and Chemical Reactions SciPack. It investigates the basics of cellular metabolisms in plants and animals.

Chemical reactions occur in all cells, are fundamental to cell functions, and are essential to maintain the chemical...  [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 Cells and Chemical Reactions SciPack. It investigates the basics of cellular metabolisms in plants and animals.

Chemical reactions occur in all cells, are fundamental to cell functions, and are essential to maintain the chemical and physical organization of living systems. All living organisms engage in metabolic processes that take place inside their cells. Metabolism refers to all of the chemical activities and reactions in cells and organisms that are necessary for life. Metabolic processes can be categorized into two types, which are distinguished by their function in growth and maintenance of living cells: synthesis, chemical reactions that use energy to synthesize large and complex carbon-based molecules from smaller molecules; decomposition, chemical reactions that release energy from chemical bonds by decomposing the large molecules into smaller, simpler and lower-energy molecules. The energy released in decomposition is used to synthesize large molecules and in other cellular work, including: movement, maintenance and organization, transport of molecules, and transmission of nerve impulses. A large set of protein catalysts, called enzymes are required for both synthesis and decomposition chemical reactions. Because all matter tends toward disorganized states, constant input of energy is required by all cells to maintain chemical and physical organization. Without this organization, cells and organisms die, and with death (the cessation of energy input) living systems rapidly disintegrate.
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Ocean's Effect on Weather and Climate: Global Precipitation and Energy
 Science Object
Science Object
Ocean's Effect on Weather and Climate: Global Precipitation and Energy
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 NOAA and NSTA, is the second of four Science Objects in the Ocean’s Effect on Weather and Climate SciPack. It explores the distribution of water and energy on Earth. The cycling of water in and out of the atmosphere and oceans affects Earth’s climates by influencing...  [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 Ocean’s Effect on Weather and Climate SciPack. It explores the distribution of water and energy on Earth. The cycling of water in and out of the atmosphere and oceans affects Earth’s climates by influencing patterns of precipitation and by transferring energy between the oceans and the atmosphere. As water moves through the water cycle, it evaporates from Earth’s surface, rises and cools, condenses into rain, snow, or ice, and falls back to the surface. The water falling on land collects in rivers and lakes, soil, and porous layers of rock, and much of it eventually flows back into the ocean. The water cycle connects the oceans to all of Earth’s water reservoirs via evaporation and precipitation. The ocean loses thermal energy due to the evaporation of water. This energy transfer drives atmospheric circulation as water moves to the atmosphere as vapor and eventually condenses, releasing thermal energy to the surrounding air.
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Ocean's Effect on Climate and Weather: Global Circulation Patterns
 Science Object
Science Object
Ocean's Effect on Climate and Weather: Global Circulation Patterns
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 NOAA and NSTA, is the third of four Science Objects in the Ocean’s Effect on Weather and Climate SciPack. It explores ocean circulation patterns and the effect oceans have on climate. Water in the oceans hold a lot of thermal energy (more than an equal amount of...  [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 Ocean’s Effect on Weather and Climate SciPack. It explores ocean circulation patterns and the effect oceans have on climate. Water in the oceans hold a lot of thermal energy (more than an equal amount of land). Throughout the ocean there is a global, interconnected circulation system that transfers this thermal energy across Earth. The shape of ocean basins and adjacent land masses influence the path of circulation. As ocean currents transfer thermal energy to various locations, the temperature of the atmosphere above the ocean is affected. For example, the condensation of water that has been evaporated from warm seas provides the energy for hurricanes and cyclones. When the pattern of thermal energy released into the atmosphere changes, global weather patterns are affected. An example of a large-scale change like this is the El Niño Southern Oscillation, which changes the pattern of thermal energy released into the atmosphere in the Pacific.
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Atomic Structure: Investigating Atoms Science Object
Science Object
Atomic Structure: Investigating Atoms
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 Atomic Structure SciPack. It discusses the basics of atomic structure and how we know what we know about atoms. Atoms are made of a positive nucleus surrounded by negatively charged electrons. The nucleus is a tiny fraction of the volume...  [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 Atomic Structure SciPack. It discusses the basics of atomic structure and how we know what we know about atoms. Atoms are made of a positive nucleus surrounded by negatively charged electrons. The nucleus is a tiny fraction of the volume of an atom but makes up almost all of its mass. The nucleus is composed of protons and neutrons, which have roughly the same mass but differ in that protons are positively charged while neutrons have no electric charge. Isotopes of the same element have the same number of protons (and therefore of electrons) but differ in the number of neutrons. The electric force between the nucleus and electrons holds the atom together.
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Atomic Structure: Energy in Atoms Science Object
Science Object
Atomic Structure: Energy in Atoms
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 three Science Objects in the Atomic Structure SciPack. It investigates the forces at work within the nuclei of atoms and the energy contained in within atomic nuclei. Scientists continue to investigate atoms and have discovered even smaller constituents of which neutrons...  [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 three Science Objects in the Atomic Structure SciPack. It investigates the forces at work within the nuclei of atoms and the energy contained in within atomic nuclei. Scientists continue to investigate atoms and have discovered even smaller constituents of which neutrons and protons are made. The nuclear forces that hold the nucleus of an atom together, at nuclear distances, are almost always stronger than the electric forces that would make it fly apart. Nuclear reactions convert a fraction of the mass of interacting particles into energy, and they can release much greater amounts of energy than interactions between atoms. Fission is the splitting of a large nucleus into smaller pieces. Fusion is the joining of two nuclei at extremely high temperature and pressure, and is the process responsible for the energy of the sun and other stars. Energy is released whenever the nuclei of very heavy atoms, such as uranium or plutonium, split into middleweight ones, or when very light nuclei, such as those of hydrogen and helium, combine into heavier ones.
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