Biology · Lesson Worlds
Genetics: interactive science lab
Change how common the dominant allele is and prove that the visible trait can show up even when it is not the only gene in the tray.
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What will you learn?
A dominant allele can hide a recessive one. Raise the dominant share and more offspring show that trait.
How does the lab work?
Observe the simulation, make a prediction, change a variable, run the experiment, and explain the result. Finish with a challenge that tests your understanding.
You can change: Dominant allele. Compare what happens and connect the result to the scientific explanation.
Try a comparison in Genetics
Start with the lab’s initial settings. Choose one control below, predict the result, and change that control while keeping the others fixed. Record the setting and what you observe before making a second change.
- Dominant allele: the lab starts at 0.5; its available range is 0.1–1.
For a named starting condition, try Rare, Room, Common. A preset can change several settings: check the controls before treating two presets as a one-variable comparison.
Questions to discuss during the activity
- Watch what happens. Some show the dominant color. Some do not. Watch a mixed tray.
- Name the cause. If the allele is dominant, one copy paints the trait. Recessive only shows when both copies are recessive. Load the tray with dominant alleles and most offspring show the paint. One copy can be enough to show.
- Change something. Raise the dominant allele and more squares should take that color. Change the dominant share, then cross.
- Guess before you run. If we raise the dominant allele to 0.9, the tray will look… Guess what will happen, then run to check.
After your comparison, explain how the observations connect to this idea: A dominant allele can hide a recessive one. Raise the dominant share and more offspring show that trait. Name one condition you held fixed and one feature of the real world this model simplifies. A completed run is a starting point for discussion, rather than proof of mastery.
Who is it for?
Curious learners exploring biology. A parent or teacher can help younger learners read the instructions and discuss the results. Choose by topic and prior knowledge rather than a fixed grade level.
Is this lab free?
Yes. This interactive lab is free without signing in or a paid membership.
No app download is needed; interactive play requires JavaScript and a modern browser.
Use this activity with a learner
Families and educators · choose by prior knowledge
Learning goal: A dominant allele can hide a recessive one. Raise the dominant share and more offspring show that trait.
Before you begin: Read the controls for Dominant allele. Make one prediction before changing a setting.
Check understanding: Ask for one observation, the evidence that supports it, and a question to investigate next.
A simulation simplifies the real world. Explain which conditions stayed fixed; a successful run alone does not demonstrate mastery.
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