EXPLORE · PRACTICE · EXPLAIN
Explain how a bone works or trace a change through a kelp forest. Start with eight original questions right here; no account or game PIN is needed.
These are practice activities, not formal tests. Try each question in your own words before opening its explanation.
Choose one topic and allow 6–8 minutes. Work independently: write a one- or two-sentence answer in a notebook, or say it aloud. Then open Check the explanation and revise one part of your reasoning. With a partner, compare your explanations after both of you have tried.
ANATOMY / FOUR QUESTIONS
Connect the material inside a bone to support, blood-cell production, and renewal.
A cutaway shows a dense outer wall and a network of struts inside a bone. A learner calls the inside “soft packing.” What would you correct?
Spongy bone is mineralized tissue, not a soft sponge. Its struts, called trabeculae, form a supporting network with spaces between them. This arrangement provides strength without filling the whole bone with dense tissue. Compact bone forms the dense outer layer; many bones contain both types.
Red marrow and yellow marrow are both found inside bones. Why would it be misleading to label both simply “blood-cell factories”?
Red marrow contains the cells that produce blood cells. Yellow marrow contains much more fat and serves mainly as an energy reserve. Their proportions and locations change with age. Marrow is tissue within bone spaces; it is not the hard bone matrix around those spaces.
A model represents bone using a flexible framework reinforced with hard material. Which two bone components does this model help you explain, and where does the comparison stop?
Collagen contributes a protein framework and flexibility; mineral, largely calcium phosphate, contributes hardness and resistance to compression. Both matter to bone’s mechanical behavior. The model can illustrate those complementary roles, but it leaves out living cells, blood vessels, and the continuous renewal of real tissue.
An adult’s height stays the same for a year. Does that show that the person’s bones have stopped changing? Explain the role of two kinds of bone cells.
No. Bone remodeling continues after growth in height stops. Osteoclasts remove existing bone tissue, and osteoblasts form new tissue. Coordinated removal and replacement renew bone without necessarily changing its overall length. A stable height tells you little about this cellular activity.
Make it visible: sketch a bone cross-section in your notebook. Label compact bone, spongy bone, and a marrow space; add a sentence explaining how one feature supports a function.
Check the science: OpenStax: Bone Structure · NIH/NIAMS: What Is Bone?
Explore the virtual bone lab →ENVIRONMENTAL SYSTEMS / FOUR QUESTIONS
Use a simple chain to reason about a larger ecosystem, then consider what the chain leaves out.
Draw a food-energy chain for kelp, sea urchins, and sea otters. Explain what an arrow means, including why it does not point from hunter to food.
The chain is kelp → sea urchin → sea otter. An arrow points from the food to the consumer, showing energy transferred through feeding. Kelp uses sunlight to make food; urchins graze on kelp, and otters can eat urchins. This chain shows only part of their diets and food web.
Suppose otter numbers fall where otters eat kelp-grazing urchins. Predict a possible later change in kelp, and explain the intermediate step.
With less otter predation, urchins may become more abundant or graze more heavily, reducing kelp. Otters affect kelp indirectly through the grazers. This connection across feeding levels is a trophic cascade. It is a possible pathway, not a guarantee of the same outcome at every coast.
Two places have similar otter numbers but different amounts of kelp. Suggest one additional factor to investigate and explain why it could matter.
One useful choice is water temperature: kelp generally thrives in cool, nutrient-rich water, and unusually warm conditions can limit growth. Light, storms, and other grazers also matter. Compare these conditions over time before deciding that otter numbers alone explain the difference.
You replay the same programmed lab sequence three times and see the same result. Does that establish what will happen at a real coastline? Name evidence you would still need.
Replaying demonstrates the model’s programmed behavior; it is not three independent field observations. A stronger real-world investigation would track otters, urchin grazing, kelp cover, and environmental conditions at multiple sites over time. The model helps form a prediction, while field evidence helps test it.
Make it visible: draw two small panels labeled “Otters present” and “Fewer otters.” Add the urchin and kelp changes you predict, then name one condition that could change your prediction.
Check the science: NOAA: Aquatic food webs · NOAA: What is a kelp forest? · National Park Service: Kelp Forests
Investigate with the kelp forest lab →OPTIONAL / EXTERNAL GAMES
Each visual review has 20 questions with 60 seconds per question. You can complete the self-checks above without opening either game.
ANATOMY / SKELETAL SYSTEM
Connect bone structure with its job. Review skeletal functions, axial and appendicular divisions, bone shapes, compact and spongy bone, and red and yellow marrow.
20 multiple-choice questions · 60 seconds each
Open Anatomy Kahoot ↗
ENVIRONMENTAL SYSTEMS / FOOD WEBS
Follow the links between sea otters, sea urchins and kelp. Practice food-energy arrows, direct and indirect effects, data-based predictions, conservation choices and model limits.
20 multiple-choice questions · 60 seconds each
Open ES Kahoot ↗Playing with your class? Wait for your teacher’s game PIN and enter it at kahoot.it. The review buttons open Kahoot in a new tab; sign-in or play options may vary by account and device.