Keep a living culture breathing. Lay oxygen-secreting feeder cells, start the clock, and let a real cell-growth model decide what survives.
Sixteen experiments across five chapters, two of them out in a jar of pond water and on a forest floor, a sandbox, and four habitats on a big dish: a lab plate, a pond, a forest floor and a hardcore kitchen counter, with photosynthetic, bone, blood and immune cells against bacteria and fungi, and a dozen microbes from pond water, leaf litter and the kitchen. Under the hood: oxygen diffusion, cell division, crowding and cell death from the PhysiCell agent-based model of cultured tissue. Runs in your browser; progress is saved on this device.
Design scaffold
Day 0 · 00:00
steady-state O₂ preview
O₂ (mmHg)
051538
100 µm
Hover the dish to probe oxygen
Harvest
Leaderboard
#
Who
Cell-days
Lasted
Posted
Kitchen Counter leaderboard
One kitchen for everyone: the same counter, the same spills and the same wipes at the same times. The score is cell-days, every living culture cell counted for each hour it stays alive.
#
Who
Cell-days
Lasted
Posted
Paste a coords.csv
One cell per row as x, y, z, type. Rows of type 3 become feeder cells. Coordinates are microns from the dish centre.
Reset progress?
This clears every star, best yield and saved scaffold on this device.
What's under the lens
Culture cells divide about every 16 hours when oxygen is plentiful. Each carries its own growth drive (its oncoprotein level, drawn at random around 1), so some divide faster than others.
Division slows as oxygen falls from 38 mmHg and stops at 5 mmHg. Below 5 mmHg cells start to die (necrosis), fastest at 2.5 mmHg. Dead cells swell and take up space until you clear them.
Oxygen diffuses across the dish and decays. Culture cells breathe it; feeder cells are fixed in place and release it, but they take up room the culture could have used. An open dish also gets oxygen through its rim.
Cells push and stick to each other. A crowded cell stops dividing, so the tissue stays one layer thick.
Wild cells are a contaminant this game adds: they divide faster, breathe harder, keep growing at low oxygen and poison the culture cells they press against.
Your score is the yield: the total volume of living culture cells at harvest, in nanolitres (1 nL is a million cubic microns).
Interventions
O₂ perfusion pipes oxygen into one spot for 12 hours.
Debride washes dead cells out of a 50 µm circle.
Growth factor multiplies the growth drive of living cells in a 50 µm circle by 1.5. Faster growth also burns more oxygen.
Antibiotic kills every wild cell and bacterium in a 60 µm circle. In a habitat a Bacillus spore survives it, and so does most of a biofilm.
Antifungal (habitats and the field) kills every fungal thread in a 60 µm circle, and in a habitat the moulds' threads and yeast too.
Habitats
The habitats run on a 1.8 mm dish and add a whole cast to the culture. None of it is in the original model: it is this game's own, built on the same oxygen, division and mechanics rules.
Photosynthetic cells make oxygen and sugar in light and breathe a little all the time. Light fills an energy store and darkness drains it; a cell kept dark too long dies.
Bone is fixed and stiff, so tissue holds to it and a frame of it keeps a body in shape. Its marrow makes circulatory cells, faster when the tissue is short of oxygen, and immune cells, faster and in greater numbers when invaders are about.
Vessels grow the way capillaries do. Starving tissue calls for them (the hunger signal plays the part of VEGF): a vessel's tip climbs that signal at up to about 20 µm an hour, new sprouts branch off steeply but never beside another tip or into ground a vessel already serves, and a tip that meets another vessel fuses with it into a loop. A branch that feeds no starving tissue and carries no blood, or is cut off from the vessel you laid, withers within half a day (two days once it is two days old). Laid vessels are fed by the dish's circulation and stay. Drawn width follows Murray's law: a trunk is as thick as the branches it feeds.
Circulatory cells never divide, and travel only inside vessels and bone marrow. Empty, they head toward oxygen and sugar and load up; full, they follow the hunger signal of starving tissue and unload where it calls. So a body needs a vessel out to rich water (its lung) as well as vessels into the tissue. One spilled out of every vessel stops, carries nothing and is cleared. Bright red means loaded, dark means empty.
Immune cells leave the vessels to hunt, but never more than 200 µm from a vessel or bone. They follow the alarm signal that invaders and dying cells give off, kill the bacteria, wild cells and fungal threads they touch, and eat the dead. Now and then one kills a healthy cell instead, more often where the alarm is loud.
Bacteria are small and multiply fast on sugar, slower without oxygen, starve without sugar and poison the tissue they touch.
Fungi grow as fixed threads from their tips, branch, throw spores, digest the dead, and take several immune hits to kill.
Every habitat has a sugar field beside the oxygen one, fed by the medium, by photosynthesis and by rotting leaves and crumbs (fungi and bacteria rot them faster). Culture cells need sugar to divide and starve without it.
In the sandboxes you can set things down as well as cells. Leaves and crumbs feed the sugar field as they rot. A rock is solid: no cell grows on it or passes through it, and oxygen, sugar and signals have to flow round it, so a ring of rocks walls off whatever is inside. Copper is solid like a rock, and bacteria and yeast that touch it or stray within 25 µm of it (the faint ring round it) soon die, though a Bacillus spore shrugs it off; nothing else is harmed.
Drag with the probe tool, or with two fingers, or hold WASD or the arrow keys, to move around; scroll or use the buttons on the dish to zoom.
Microbes
The habitats also offer the microbes that live there: pond water, leaf litter, a kitchen counter, and all of them on the Big Dish. Each follows its real organism's biology, simplified, and like the rest of the cast they are this game's own. The big ones are drawn smaller than life: a real Paramecium is some fifteen culture cells long.
Paramecium follows the scent of bacteria and sweeps them, and yeast, into its mouth with its cilia. It divides when well fed and starves without prey.
Didinium hunts only Paramecium and swallows one whole. Once they are gone, about half curl into cysts, and a cyst wakes when a Paramecium comes near.
Rotifers are micro-animals of about a thousand cells, not single cells. One crawls, then anchors and pulls bacteria, yeast and algae in with its crown of cilia, and lays eggs that hatch a day later.
Euglena makes its own food in light and swims toward it, gathering where sunflecks fall. In the dark it lives on sugar; with neither, it starves.
Bdellovibrio is a predatory bacterium. It enters a bacterium or a Pseudomonas, grows inside it and bursts out as four; without prey it dies within hours.
Baker's yeast ferments sugar into ethanol even with oxygen about. The ethanol kills bacteria, slows tissue, and in the end stops the yeast itself, which then lives on the ethanol once the sugar is gone. On the Kitchen Counter it is a trap: it gets to the spilled sugar before the tissue does, and a counter left to yeast is lost sooner.
Penicillium grows as threads and seeps penicillin, which kills Bacillus and spares Pseudomonas, whose outer membrane keeps it out. On the Kitchen Counter a ring of it keeps an undefended smear alive longer.
Bacillus, out of sugar, becomes a spore that survives antibiotic and copper and clings through most wipes, and wakes when sugar is back.
Agar (Big Dish only) shapes a Bacillus colony, after a published model of real Bacillus plates: harder agar slows the cells, used-up sugar stops them, and in a dense colony they can switch to swarming together. On hard agar with plenty of sugar a colony grows as a dense disk; on soft agar it spreads thin over the whole dish. How fast they move on each agar is the game's own choice, and the game grows only those two shapes: real plates also grow rings and branches.
Pseudomonas ignores penicillin. Crowded past a quorum, its signal turns it to biofilm: slime that takes in other bacteria and shields them from most of a dose.
The slime mould Dictyostelium hunts bacteria as single amoebae. Starved, they call each other in with cAMP: each amoeba answers a pulse with its own and then rests a few minutes, so the call spreads in waves. They gather into a mound, which crawls off as a slug toward the light, its future stalk cells in front, then builds a fruiting body: a stalk of dead cells holding up spores.
Trichoderma is a mould that hunts other moulds: its threads grow toward another fungus's threads, coil round them and kill them.
Myxococcus hunts as a pack. A crowd of it seeps enzymes that dissolve bacteria and yeast, and shares the meal; one alone can do little.
Antibiotic and copper kill the bacterial microbes, antifungal kills yeast and the moulds' threads, and copper kills yeast too. Immune cells swallow yeast and the bacterial microbes and leave the ciliates, rotifers and Euglena alone. The field menu under the dish shows the microbes' own fields where they are about: prey scent, ethanol, penicillin, the quorum signal, cAMP and the pack's lytic enzymes.
Out in the field
The Pond Water and Forest Floor chapters open with the first experiment's first star. They are scored like any experiment, on the culture living at harvest, but you build from a fixed kit (its budgets are listed under each brief) instead of laying feeder cells: algae in a sealed jar, rotting leaves on the forest floor, copper against bacteria and rocks against mould. They run on the habitats' rules above, and like the habitats they are this game's own.
Controls
Spacestart, pause or resume the culture1to 9 pick a toolFfast-forwardCtrl Zundo the last scaffold stroke+and - zoom a habitat dishW A S Dor the arrow keys: move around a habitat dish (hold Shift to go faster)Msound on or offEscclose a window
The model
The simulation follows the PhysiCell agent-based model (oxygen on a 20 µm grid solved like BioFVM, the oxygen-driven division and necrosis rule, and potential-based cell mechanics) as set up by a cultured-meat scaffold project. The experiments use a denser tissue than that project's defaults (three times the oxygen uptake, four times the feeder output) so the scaffold decides the outcome; Free Play starts from the original values. Contact inhibition, the wild strain and the interventions are this game's additions. Runs are deterministic: the same scaffold and the same clicks give the same culture.