The vocabulary designers meet when they work with living materials, defined in plain words. Most entries go one step further than a definition: they say what the definition alone does not tell you, which is usually where a claim outruns its evidence.
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A mat of pure cellulose fibres built outside the cell by bacteria, usually Komagataeibacter, at the surface of a sugary liquid. It is the material behind kombucha leather.
Most claims about its strength describe the wet mat. Almost all of them are tested after drying.
What accumulates from doing the reasoning repeatedly: knowing which claims to trust, which to test, and which to keep as deliberate speculation rather than mistake for a working material.
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Design that works with living systems and the materials they grow. The designer sets up and tends the conditions in which an organism makes the material, rather than shaping one that arrives finished.
The word is shared with medical-device biodesign, taught at Stanford. Both apply design method to biology, and there the resemblance stops: different materials, different literatures, colliding search results.
The sentence about what a living material does that a design project has come to rely on. “This mycelium heals its own cracks.” It names an effect, and it usually arrives unchosen, picked up from a paper or a supervisor.
One word can hide five unrelated behaviours. “Self-heals” is the usual example.
Letting an organism grow the material in conditions you tend, rather than shaping a material that is already made.
The word covers everything from a kombucha mat to printed human tissue. Wikipedia’s definition is automated and medical. Dezeen’s is anything grown.
Citrate is the dissolved form of citric acid in a bacterial cellulose recipe. Recipes say citric acid, papers say citrate, and they are not the same molecule. Citrate is the one that bacteria meet.
Called a buffer in protocols since the 1980s, usually without a test.
When something added to keep one part of an experiment steady also changes another biologically important part of the system. The control still does its job. That is what makes it easy to miss.
Changing the variable you are testing can change the control’s chemistry along with it. Holding a buffer’s concentration constant is not the same as holding its effects constant.
A change caused by previous conditions that persists in a living material and can influence its response to later conditions. Two runs can share the same final recipe and begin with organisms prepared differently.
The tests that establish how a material behaves can become part of its preparation. Calibration can change the material being calibrated.
The liquid a culture is grown in: a sugar source, a nitrogen source, water, and whatever else the recipe inherited.
Calcium sulfate dihydrate, added to mushroom substrate and mycelium recipes. It keeps grain from clumping, supplies calcium and sulfur, and is very often described as a pH buffer.
A buffer resists a change in pH. What was actually measured is gypsum lowering pH in one kind of compost, which is a different thing. The chemistry offers no buffering capacity either.
The buffer in many cyanobacteria and algae recipes. It is added to keep the pH from drifting as the cells feed and change the water around them. Under light, and with help from the medium, HEPES also makes hydrogen peroxide.
Whether HEPES matters depends on who is there to clear the peroxide. A crowded culture can. A thinly seeded one cannot, unless a neighbouring organism steps in.
A causal explanation in a protocol, growing more specific with each retelling while the evidence behind it stays the same. Nothing is invented. The explanation just thickens.
Walk one inherited sentence back through its sources. If every step added a sentence and none added a measurement, that is what you are looking at.
The ability to read a claim about a living material and see the biology it depends on: what is doing the work, what sets it off, and what evidence would show it is real. It is a reading skill before it is a making skill.
Often taken to mean lab skill. It is closer to reading a label than to running a protocol.
Literacy put to work: tracing a design intention downward until you reach the molecule, protein or organism the intention actually rests on. You go as deep as the claim needs and stop there.
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A behaviour that several conditions produced together, written down as a property of one ingredient or organism. Move it somewhere else and the behaviour does not come with it.
The short version fits a protocol table, a database field and a model variable. The version with the conditions attached fits none of them. That is why the short one travels.
A correct account of what an ingredient does in a living system, taken for the complete account. The label is right, which is what makes a swap look safer than it is.
Nothing here is false, so a fact check finds nothing wrong. A correct label still narrows what anyone thinks to test, and makes a swap look safer than it is.
Structural colour is the colour produced by the physical arrangement of a material rather than by a pigment or dye. The arrangement reflects, redirects and scatters light so that some wavelengths reach the eye more strongly than others.
Usually offered as colour without dye, and so as the sustainable choice. Nothing here is coloured though, so the colour lasts only as long as the arrangement holds.
