Gallery
Discover apps people built on Collabby by chatting. Run them, then remix to make them yours.
The Flow of Genetic Information
One base can rewrite life's blueprint — transcribe 9 DNA bases into mRNA base by base, translate 3 codons into a Met-Tyr peptide using the codon table, then swap a single base to compare silent, missense, and nonsense mutations.
Homeostasis: Negative Feedback
See how negative feedback brings the body back to normal: when body temperature rises, we sweat; when it falls, we shiver—returning to 36.5°C. When blood sugar rises, insulin is released; when it falls, glucagon helps restore a healthy range.
Stimulus and Response
In Signal Path, you have to set the order to sensory neuron → association neuron → motor neuron yourself before a signal can travel all the way to a response — get the order wrong and it stops partway. You'll also see that a reflex skips the brain, bouncing straight back from the spinal cord, which is why it's faster. In Nerve vs. Hormone, compare how a nerve signal is fast but reaches only one place, while a hormone is slow but spreads through the blood to many places at once — growth hormone, insulin, glucagon, and thyroxine all work this way. In Blood Sugar, raise and lower blood sugar by eating, exercising, and letting time pass, then switch off insulin or glucagon and watch blood sugar get stuck away from its normal level of 100. Keeping the body steady turns out to be teamwork between nerves and hormones.
Mitosis and Meiosis
In Grow the Cell, increase a cube-shaped cell's side length from 1 and watch volume grow by the cube while surface area grows only by the square — surface area ÷ volume starts at 6 and keeps shrinking, which is exactly why cells need to divide. In Body Cells, walk through mitosis: chromosomes (2n=4) copy themselves, line up in the middle, then pull apart into 2 daughter cells that each keep 2n=4. In Sex Cells, two divisions halve the chromosome count (2n→n) to make 4 cells. That halved number gets restored to 2n only when fertilization happens.
Microbes and Classifying Life
In Zoom In, pick mold, paramecium, or E. coli and raise the magnification up to ×1000 to reveal microbes invisible to the naked eye. In Which Group?, read clues like "no roots, stems, or leaves" to sort 9 living things into fungi, protists, and bacteria — mold as a fungus, paramecium as a protist, E. coli as a bacterium. In Good or Bad, adjust temperature and humidity over 4 days: the very same microbes can turn ingredients into kimchi, soybean paste, or bread — or spoil that same food under different conditions. Microbes aren't simply good or bad; how they act depends on the conditions you set.
Ecological Pyramids & Population Growth
At every step up the food chain 90% of the energy is lost as heat and only 10% moves on. Watch the pyramid narrow from producers to tertiary consumers, compare runaway exponential growth when resources are endless with the S-shaped curve when they run short, then change the carrying capacity and see where the population settles.
Genetic Crosses
A single dominant allele is enough for the dominant trait to show. Check the phenotypes of RR, Rr and rr, read the 3 : 1 ratio of an Rr × Rr cross straight off a Punnett square, then actually draw offspring and watch the observed ratio close in on theory as the sample grows.