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- Life Science (2007)
Life Science (2007)
Unit 1: The Study of Living Things
Chapter 3: Light and Living Things
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Additive Colors
Control the intensity of red, green, and blue spotlights. Additive colors can be observed where the spotlights overlap. The RGB value of any point can be measured. Just about any color can be created by mixing varying amounts of red, green, and blue light. 5 Minute Preview
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Basic Prism
Shine white light or a single-color beam through a prism. Explore how a prism refracts light and investigate the factors that affect the amount of refraction. The index of refraction of the prism, width of the prism, prism angle, light angle, and light wavelength can be adjusted. 5 Minute Preview
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Herschel Experiment
Shine sunlight through a prism and use a thermometer to measure the temperature in different regions of the spectrum. The thermometer can be dragged through the visible spectrum and beyond. This recreates the experiment of William Herschel that led to the discovery of infrared radiation in 1800. 5 Minute Preview
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Laser Reflection
Point a laser at a mirror and compare the angle of the incoming beam to the angle of reflection. A protractor can be used to measure the angles of incidence and reflection, and the angle of the mirror can be adjusted. A beam splitter can be used to split the beam. Both plane and irregular mirrors can be used. 5 Minute Preview
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Ray Tracing (Lenses)
Observe light rays that pass through a convex or concave lens. Manipulate the position of an object and the focal length of the lens and measure the distance and size of the resulting image. 5 Minute Preview
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Refraction
Determine the angle of refraction for a light beam moving from one medium to another. The angle of incidence and each index of refraction can be varied. Using the tools provided, the angle of refraction can be measured, and the wavelength and frequency of the waves in each substance can be compared as well. 5 Minute Preview
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Subtractive Colors
Move spots of yellow, cyan, and magenta pigment on a white surface. As the colors overlap, other colors can be seen due to color subtraction. The color of most things you see--such as cars, leaves, paintings, houses, and clothes--are due to color subtraction. The intensity of the cyan, magenta, and yellow can be adjusted, and the RGB value at any location can be measured. 5 Minute Preview
Unit 2: Cells
Chapter 4: Cells: The Basic Units of Life
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Cell Structure
Select a sample cell from an animal, plant, or bacterium and view the cell under a microscope. Select each organelle on the image to learn more about its structure and function. Closeup views and animations of certain organelles is provided. 5 Minute Preview
Chapter 5: The Cell in Action
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Cell Division
Begin with a single cell and watch as mitosis and cell division occurs. The cells will go through the steps of interphase, prophase, metaphase, anaphase, telophase, and cytokinesis. The length of the cell cycle can be controlled, and data related to the number of cells present and their current phase can be recorded. 5 Minute Preview
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Cell Energy Cycle
Explore the processes of photosynthesis and respiration that occur within plant and animal cells. The cyclical nature of the two processes can be constructed visually, and the simplified photosynthesis and respiration formulae can be balanced. 5 Minute Preview
Unit 3: Heredity and Genes
Chapter 6: Heredity
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Chicken Genetics
Breed "pure" chickens with known genotypes that exhibit specific feather colors, and learn how traits are passed on via codominant genes. Chickens can be stored in cages for future breeding, and the statistics of feather color are reported every time the chickens breed. Punnett squares can be used to predict results. 5 Minute Preview
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Mouse Genetics (One Trait)
Breed "pure" mice with known genotypes that exhibit specific fur colors, and learn how traits are passed on via dominant and recessive genes. Mice can be stored in cages for future breeding, and the statistics of fur color are reported every time a pair of mice breed. Punnett squares can be used to predict results. 5 Minute Preview
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Mouse Genetics (Two Traits)
Breed "pure" mice with known genotypes that exhibit specific fur and eye colors, and learn how traits are passed on via dominant and recessive genes. Mice can be stored in cages for future breeding, and the statistics of fur and eye color are reported every time a pair of mice breed. Punnett squares can be used to predict results. 5 Minute Preview
Chapter 7: Genes and DNA
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Building DNA
Construct a DNA molecule, examine its double-helix structure, and then go through the DNA replication process. Learn how each component fits into a DNA molecule, and see how a unique, self-replicating code can be created. 5 Minute Preview
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DNA Analysis
Scan the DNA of frogs to produce DNA sequences. Use the DNA sequences to identify possible identical twins and to determine which sections of DNA code for skin color, eye color, and the presence or absence of spots. 5 Minute Preview
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Human Karyotyping
Sort and pair the images of human chromosomes obtained in a scan. Find differences in the scans of the various patients to find out specific things that can cause disease, as well as determining the sex of the person. 5 Minute Preview
Unit 4: Earth and Life History
Chapter 9: The History of Life on Earth
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Human Evolution - Skull Analysis
Compare the skulls of a variety of significant human ancestors, or hominids. Use available tools to measure lengths, areas, and angles of important features. Each skull can be viewed from the front, side, or from below. Additional information regarding the age, location, and discoverer of each skull can be displayed. 5 Minute Preview
Chapter 10: The Evolution of Living Things
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Microevolution
Observe the effect of predators on a population of parrots with three possible genotypes. The initial percentages and fitness levels of each genotype can be set. Determine how initial fitness levels affect genotype and allele frequencies through several generations. Compare scenarios in which a dominant allele is deleterious, a recessive allele is deleterious, and the heterozygous individual is fittest. 5 Minute Preview
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Natural Selection
You are a bird hunting moths (both dark and light) that live on trees. As you capture the moths most easily visible against the tree surface, the moth populations change, illustrating the effects of natural selection. 5 Minute Preview
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Rainfall and Bird Beaks
Study the thickness of birds' beaks over a five-year period as you control the yearly rainfall on an isolated island. As the environmental conditions change, the species must adapt (a real-world consequence) to avoid extinction. 5 Minute Preview
Unit 5: Structure and Function in Plants and Animals
Chapter 13: Plant Processes
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Pollination: Flower to Fruit
Label a diagram that illustrates the anatomy of a flower, and understand the function of each structure. Compare the processes of self pollination and cross pollination, and explore how fertilization takes place in a flowering plant. 5 Minute Preview
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Seed Germination
Perform experiments with several seed types to see what conditions yield the highest germination (sprouting) rate. Three different types of seeds can be studied, and the temperature, water and light in the germination chamber can be controlled. No two trials will have the same result so repeated trials are recommended. 5 Minute Preview
Unit 6: Human Body Systems
Chapter 17: Communication and Control
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Hearing: Frequency and Volume
Test your hearing range by listening to low-, medium-, and high-frequency sounds. Compare the relative loudness of sounds at each frequency to create an equal-loudness curve. In a quiet room, measure your threshold of audibility for each frequency, and compare your results to others. The volume of each sound can be adjusted. 5 Minute Preview
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Reverse the Field
Measure the time required to write a word when the mouse behaves in a normal fashion and when the direction of motion is reversed from left to right, up to down, or both. Run several experiments in each mode to see if your brain and muscles are able to adapt to the new direction of motion. Determine which type of inversion is easiest to adjust to and whether you can train yourself to function normally when the inversion is present. 5 Minute Preview
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Sight vs. Sound Reactions
Measure your reaction time by clicking your mouse as quickly as possible when visual or auditory stimuli are presented. The individual response times are recorded, as well as the mean and standard deviation for each test. A histogram of data shows overall trends in sight and sound response times. The type of test as well as the symbols and sounds used are chosen by the user. 5 Minute Preview
How Free Gizmos Work
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Start teaching with 20-40 Free Gizmos. See the full list.
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Access lesson materials for Free Gizmos including teacher guides, lesson plans, and more.
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All other Gizmos are limited to a 5 Minute Preview and can only be used for 5 minutes a day.
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Free Gizmos change each semester. The new collection will be available January 1 and July 1.
About STEM Cases
Students assume the role of a scientist trying to solve a real world problem. They use scientific practices to collect and analyze data, and form and test a hypothesis as they solve the problems.
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Each STEM Case uses realtime reporting to show live student results.
Introduction to the Heatmap
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STEM Cases take between 30-90 minutes for students to complete, depending on the case.
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Student progress is automatically saved so that STEM Cases can be completed over multiple sessions.
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Multiple grade-appropriate versions, or levels, exist for each STEM Case.
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Each STEM Case level has an associated Handbook. These are interactive guides that focus on the science concepts underlying the case.
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