Tennessee - Science: 7th Grade

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

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

Circulatory System

Trace the path of blood through a beating heart and the network of blood vessels that supplies blood to the body. Take blood samples from different blood vessels to observe blood cells and measure the levels of oxygen, carbon dioxide, sugar, and urea. 5 Minute Preview

Digestive System

Digestion is a complex process, involving a wide variety of organs and chemicals that work together to break down food, absorb nutrients, and eliminate wastes. But have you ever wondered what would happen if some of those organs were eliminated, or if the sequence was changed? Can the digestive system be improved? Find out by designing your own digestive system with the Digestive System Gizmo. 5 Minute Preview

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

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

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

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

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

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

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

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

Inheritance

Create aliens with different traits and breed them to produce offspring. Determine which traits are passed down from parents to offspring and which traits are acquired. Offspring can be stored for future experiments or released. 5 Minute Preview

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

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

Density Experiment: Slice and Dice

Drop a chunk of material in a beaker of water and observe whether it sinks or floats. Cut the chunk into smaller pieces of any size, and observe what happens as they are dropped in the beaker. The mass and volume of each chunk can be measured to gain a clear understanding of density and buoyancy. 5 Minute Preview

Mineral Identification

Observe and measure the properties of a mineral sample, and then use a key to identify the mineral. Students can observe the color, luster, shape, density, hardness, streak, and reaction to acid for each mineral. There are 26 mineral samples to identify. 5 Minute Preview

Rock Cycle

Play the role of a piece of rock moving through the rock cycle. Select a starting location and follow many possible paths throughout the cycle. Learn how rocks are formed, weathered, eroded, and reformed as they move from Earth's surface to locations deep within the crust. 5 Minute Preview

Plate Tectonics

Move the Earth's crust at various locations to observe the effects of the motion of the tectonic plates, including volcanic eruptions. Information about each of the major types of plate boundaries is shown, along with their locations on Earth. 5 Minute Preview

Earthquakes 1 - Recording Station

Using an earthquake recording station, learn how to determine the distance between the station and an earthquake based on the time difference between the arrival of the primary and secondary seismic waves. Use this data to find the epicenter in the Earthquakes 2 - Location of Epicenter Gizmo. 5 Minute Preview

Plate Tectonics

Move the Earth's crust at various locations to observe the effects of the motion of the tectonic plates, including volcanic eruptions. Information about each of the major types of plate boundaries is shown, along with their locations on Earth. 5 Minute Preview

Coral Reefs 1 - Abiotic Factors

Explore the abiotic factors that affect Caribbean coral reefs. Many factors can be manipulated in this simplified reef model, including ocean temperature and pH, storm severity, and input of excess sediments and nutrients from logging, sewage, and agriculture. Click "Advance year" to see how the reef responds to these changes. 5 Minute Preview

Coral Reefs 2 - Biotic Factors

In this followup to the Coral Reefs 1 - Abiotic Factors activity, investigate the impacts of fishing, disease, and invasive species on a model Caribbean coral reef. Many variables can be manipulated, included intensity of fishing, presence of black band and white band disease, and the presence of actual and potential invasive species. Click "Advance year" to see the impacts of these biotic changes. 5 Minute Preview

Ants on a Slant (Inclined Plane)

Lift food using ants with the help of a slanted stick. The steepness of the stick, the number of ants, and the size of the item being lifted can be varied. Observe the effect of friction on sliding objects. 5 Minute Preview

Levers

Use a lever to lift a pig, turkey, or sheep. A strongman provides up to 1000 newtons of effort. The fulcrum, strongman, and animals can be moved to any position to create first-, second-, or third-class levers. 5 Minute Preview

Pulleys

Lift a variety of heavy objects (armchair, safe, piano) using pulleys and a rope. Systems of one, two, four, or six pulleys can be used. Up to six people can be used to pull on the rope, which adds force (effort). 5 Minute Preview

Wheel and Axle

Use a wheel and axle to move a heavy load. Find out how many athletes it takes to move the load under different conditions. The radii of the wheel and the axle can be adjusted to help study mechanical advantage. 5 Minute Preview

Measuring Motion

Go on an African safari and observe a variety of animals walking and running across the savanna. Videotape the animals, and then play back the videotape to estimate animal speeds. Which animals run fastest? 5 Minute Preview

Force and Fan Carts

Explore the laws of motion using a simple fan cart. Use the buttons to select the speed of the fan and the surface, and press Play to begin. You can drag up to three objects onto the fan cart. The speed of the cart is displayed with a speedometer and recorded in a table and a graph. 5 Minute Preview

Ripple Tank

Study wave motion, diffraction, interference, and refraction in a simulated ripple tank. A wide variety of scenarios can be chosen, including barriers with one or two gaps, multiple wave sources, reflecting barriers, or submerged rocks. The wavelength and strength of waves can be adjusted, as well as the amount of damping in the tank. 5 Minute Preview

Longitudinal Waves

Observe the propagation of longitudinal (compression) waves in a closed or open tube with evenly-spaced dividers. The strength and frequency of the waves can be manipulated, or waves can be observed as individual pulses. Compare the movement of dividers to graphs of displacement, velocity, acceleration and pressure. 5 Minute Preview

Ripple Tank

Study wave motion, diffraction, interference, and refraction in a simulated ripple tank. A wide variety of scenarios can be chosen, including barriers with one or two gaps, multiple wave sources, reflecting barriers, or submerged rocks. The wavelength and strength of waves can be adjusted, as well as the amount of damping in the tank. 5 Minute Preview