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- The Living Environment (2008)
The Living Environment (2008)
2: Applications of Biology
![Screenshot of DNA Analysis](/Assets/img/blank.gif)
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
3: Chemistry of Life
![Screenshot of Identifying Nutrients](/Assets/img/blank.gif)
Identifying Nutrients
Use a variety of real-world lab tests to analyze common food samples in order to determine if the food is a carbohydrate, a protein, or a lipid. Tests that can be performed include: Benedict, Lugol, Biuret, and Sudan Red. 5 Minute Preview
4: Ecosystems
![Screenshot of Food Chain](/Assets/img/blank.gif)
Food Chain
In this ecosystem consisting of hawks, snakes, rabbits and grass, the population of each species can be studied as part of a food chain. Disease can be introduced for any species, and the number of animals can be increased or decreased at any time, just like in the real world. 5 Minute Preview
![Screenshot of Plants and Snails](/Assets/img/blank.gif)
Plants and Snails
Study the production and use of gases by plants and animals. Measure the oxygen and carbon dioxide levels in a test tube containing snails and elodea (a type of plant) in both light and dark conditions. Learn about the interdependence of plants and animals. 5 Minute Preview
![Screenshot of Rabbit Population by Season](/Assets/img/blank.gif)
Rabbit Population by Season
Observe the population of rabbits in an environment over many years. The land available to the rabbits and weather conditions can be adjusted to investigate the effects of urban sprawl and unusual weather on wildlife populations. 5 Minute Preview
![Screenshot of Water Cycle](/Assets/img/blank.gif)
Water Cycle
Control the path of a drop of water as it travels through the water cycle. Many alternatives are presented at each stage. Determine how the water moves from one location to another, and learn how water resources are distributed in these locations. 5 Minute Preview
5: Populations and Communities
![Screenshot of Estimating Population Size](/Assets/img/blank.gif)
Estimating Population Size
Adjust the number of fish in a lake to be tagged and the number of fish to be recaptured. Use the number of tagged fish in the catch to estimate the number of fish in the lake. 5 Minute Preview
![Screenshot of Food Chain](/Assets/img/blank.gif)
Food Chain
In this ecosystem consisting of hawks, snakes, rabbits and grass, the population of each species can be studied as part of a food chain. Disease can be introduced for any species, and the number of animals can be increased or decreased at any time, just like in the real world. 5 Minute Preview
![Screenshot of Rabbit Population by Season](/Assets/img/blank.gif)
Rabbit Population by Season
Observe the population of rabbits in an environment over many years. The land available to the rabbits and weather conditions can be adjusted to investigate the effects of urban sprawl and unusual weather on wildlife populations. 5 Minute Preview
6: The Environment
![Screenshot of Greenhouse Effect](/Assets/img/blank.gif)
Greenhouse Effect
Within this simulated region of land, daytime's rising temperature and the falling temperature at night can be measured, along with heat flow in and out of the system. The level of greenhouse gases present in the atmosphere at any given time can be adjusted, allowing the long-term effects to be investigated. 5 Minute Preview
![Screenshot of Rabbit Population by Season](/Assets/img/blank.gif)
Rabbit Population by Season
Observe the population of rabbits in an environment over many years. The land available to the rabbits and weather conditions can be adjusted to investigate the effects of urban sprawl and unusual weather on wildlife populations. 5 Minute Preview
![Screenshot of Water Pollution](/Assets/img/blank.gif)
Water Pollution
Get to know the four main types of pollution present in the environment, and then look at a variety of real-world examples as you try to guess what type of pollution is represented by each situation. All of the real-world situations can be viewed every day in different parts of the world. 5 Minute Preview
7: Cell Structure
![Screenshot of Cell Structure](/Assets/img/blank.gif)
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
8: Cells and Their Environment
![Screenshot of Diffusion](/Assets/img/blank.gif)
Diffusion
Explore the motion of particles as they bounce around from one side of a room to the other through an adjustable gap or partition. The mass of the particles can be adjusted, as well as the temperature of the room and the initial number of particles. In a real-world context, this can be used to learn about how odors travel, fluids move through gaps, the thermodynamics of gases, and statistical probability. 5 Minute Preview
![Screenshot of Osmosis](/Assets/img/blank.gif)
Osmosis
Adjust the concentration of a solute on either side of a membrane in a cell and observe the system as it adjusts to the conditions through osmosis. The initial concentration of the solute can be manipulated, along with the volume of the cell. 5 Minute Preview
![Screenshot of Paramecium Homeostasis](/Assets/img/blank.gif)
Paramecium Homeostasis
Observe how a paramecium maintains stable internal conditions in a changing aquatic environment. Water moves into the organism by osmosis, and is pumped out by the contractile vacuole. The concentration of solutes in the water will determine the rate of contractions in the paramecium. 5 Minute Preview
9: Photosynthesis and Cellular Respiration
![Screenshot of Cell Energy Cycle](/Assets/img/blank.gif)
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
![Screenshot of Plants and Snails](/Assets/img/blank.gif)
Plants and Snails
Study the production and use of gases by plants and animals. Measure the oxygen and carbon dioxide levels in a test tube containing snails and elodea (a type of plant) in both light and dark conditions. Learn about the interdependence of plants and animals. 5 Minute Preview
10: Cell Growth and Division
![Screenshot of Cell Division](/Assets/img/blank.gif)
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
12: Mendel and Heredity
![Screenshot of Chicken Genetics](/Assets/img/blank.gif)
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
![Screenshot of Mouse Genetics (One Trait)](/Assets/img/blank.gif)
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
![Screenshot of Mouse Genetics (Two Traits)](/Assets/img/blank.gif)
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
13: DNA, RNA, and Proteins
![Screenshot of Building DNA](/Assets/img/blank.gif)
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
![Screenshot of RNA and Protein Synthesis](/Assets/img/blank.gif)
RNA and Protein Synthesis
Go through the process of synthesizing proteins through RNA transcription and translation. Learn about the many steps involved in protein synthesis including: unzipping of DNA, formation of mRNA, attaching of mRNA to the ribosome, and linking of amino acids to form a protein. 5 Minute Preview
14: Genes in Action
![Screenshot of Evolution: Mutation and Selection](/Assets/img/blank.gif)
Evolution: Mutation and Selection
Observe evolution in a fictional population of bugs. Set the background to any color, and see natural selection taking place. Inheritance of color occurs according to Mendel's laws and probability. Mutations occur at random, and probability of capture by predators is determined by the insect's camouflage. 5 Minute Preview
16: Evolutionary Theory
![Screenshot of Evolution: Natural and Artificial Selection](/Assets/img/blank.gif)
Evolution: Natural and Artificial Selection
Observe evolution in a fictional population of bugs. Set the background to any color, and see natural selection taking place. Compare the processes of natural and artificial selection. Manipulate the mutation rate, and determine how mutation rate affects adaptation and evolution. 5 Minute Preview
17: Populations Genetics and Speciation
![Screenshot of Microevolution](/Assets/img/blank.gif)
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
20: Homeostasis and the Human Body Systems
![Screenshot of Drug Dosage](/Assets/img/blank.gif)
Drug Dosage
A drug prescription must be carefully planned to maximize benefit while avoiding an overdose. In this Gizmo, you can give a patient one or more pills and monitor the levels of medication in the body through time. Based on the reaction of the patient, determine the ideal levels of medication. Create a dosage schedule so these levels are maintained through time. Four types of pills, each with a different release pattern and target organ, are available for use. 5 Minute Preview
![Screenshot of Human Homeostasis](/Assets/img/blank.gif)
Human Homeostasis
Adjust the levels of clothing, perspiration, and exercise to maintain a stable internal temperature as the external temperature changes. Water and blood sugar levels need to be replenished regularly, and fatigue occurs with heavy exercise. Severe hypothermia, heat stroke, or dehydration can result if internal stability is not maintained. 5 Minute Preview
21: Homeostasis and Human Disease
![Screenshot of Disease Spread](/Assets/img/blank.gif)
Disease Spread
Observe the spread of disease through a group of people. The methods of transmission can be chosen and include person-to-person, airborne, and foodborne as well as any combination thereof. The probability of each form of transmission and number of people in the group can also be adjusted. 5 Minute Preview
![Screenshot of Virus Lytic Cycle](/Assets/img/blank.gif)
Virus Lytic Cycle
Release a lytic virus in a group of cells and observe how cells are infected over time and eventually destroyed. Data related to the number of healthy cells, infected cells, and viruses can be recorded over time to determine the time required for the virus to mature within a cell. 5 Minute Preview
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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.
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STEM Cases take between 30-90 minutes for students to complete, depending on the case.
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