Agar Medium For Blob (Physarum), 200 Ml

Agar Medium for BLOB (200 ml)

Agar milieu pour BLOB (200 ml), Optimized Moisture Retention Enables long-term chemotaxis and maze-solving experiments without substrate desiccation, allowing students to design and execute complex behavioral hypotheses (Synthesis).

Nutrient-Neutral Formulation Idéal pour la culture du blob provides a controlled environment for evaluating specific nutrient-driven growth responses, ensuring reproducible empirical data for student laboratory reports (Application).

Standardized Gel Strength Ensures structural integrity for the mechanical placement of sclerotia and food sources, minimizing experimental variables in high-enrollment classroom settings (Understanding).

$1.80

Quick Answer: Agar Medium for BLOB (200 ml) is an agar culture medium for growing the slime mould Physarum polycephalum, nicknamed the blob. The agar gives the blob a moist surface to spread across, while a few oat flakes placed on it supply its food.

Why the Blob Needs Agar

Physarum polycephalum is neither a fungus, an animal nor a plant but an amoeboid organism in the group Amoebozoa. Its feeding stage, the plasmodium, is one giant cell with many nuclei that creeps over damp surfaces as a yellow network of veins. The nickname blob is used widely in schools, especially in French-speaking countries, and has become the common classroom name for the organism.

If its surface dries, the plasmodium shrinks back into a hard, dormant sclerotium. An agar layer in a Petri dish keeps the surface wet without flooding it. Because Physarum feeds on bacteria and particles such as rolled oats, blob cultures are usually kept on plain, low-nutrient agar, which also stops bacteria and moulds from racing ahead of the blob. The listing gives the volume, 200 ml, but not the gel strength or recipe.

At about 20 ml per standard 90 mm dish, 200 ml pours roughly eight to ten shallow plates, or a few larger trays for maze and network experiments.

Blob Experiments on Agar

Chemotaxis: placing oat flakes at different distances and recording which one the plasmodium reaches first
Maze tests, in which the blob links two food sources through the shortest route in an agar maze
Network experiments with oat flakes arranged like towns, comparing the vein network with a road or rail map
Testing avoidance of light, salt or caffeine placed on part of the agar
Reviving a dried sclerotium on moist agar and timing its return to an active plasmodium

Handling the Agar and the Culture

Pour the agar into clean Petri dishes on a level bench and let it set completely before adding a piece of plasmodium or a sclerotium.
Keep dishes closed, in the dark, at ordinary room temperature; bright light makes the plasmodium retreat or start forming spores.
Add oat flakes sparingly and remove mouldy ones, since mould spreading over the agar is the most common reason a blob culture fails.
Move a healthy piece of plasmodium to a fresh agar dish every few days; to pause the culture, let it dry on filter paper into a sclerotium and store that dry.

Specifications

Product	Agar culture medium for Physarum polycephalum
Volume	200 ml, as titled
Organism	Physarum polycephalum, the slime mould nicknamed the blob
Feeding	Separate: rolled oat flakes placed on the agar surface
Incubation	Room temperature, in the dark
Supplied format	Confirm at enquiry

Why Choose LabEquip

Blob projects are popular with secondary biology teachers and science clubs because visible results appear within a day or two. LabEquip lists this agar in its General Lab Products range; plastic Petri dishes suit it well, and orders for a whole class can be sent through the contact page.

Frequently Asked Questions

What is the blob?

The blob is the popular name for Physarum polycephalum, a slime mould. Its active stage is a single giant cell with many nuclei that moves, finds food and avoids hazards without a brain, which makes it a favourite for behaviour experiments in schools.

Does the blob feed on the agar?

Mainly no. The agar keeps the blob moist and gives it a surface to move across. Food is supplied separately, usually as a few rolled oat flakes, which also let students steer the blob towards chosen points.

How do I start a culture on the agar?

Place a small piece of an active yellow plasmodium, or a fragment of dried sclerotium moistened with a drop of water, on the set agar and add one oat flake nearby. Close the dish and keep it in the dark; growth usually shows within a day.

Why has my blob turned into a dry crust?

It has formed a sclerotium, the dormant state it enters when the agar dries out or food runs short. It is not dead. Moved onto fresh, moist agar with an oat flake, it usually becomes active again.

Why is mould growing in the dish?

Mould usually starts on old or excess oat flakes. Use only a few flakes at a time, remove any that turn fuzzy, and transfer a clean part of the plasmodium to a fresh agar dish. Clean hands and closed lids reduce contamination.

Is Physarum polycephalum safe to handle in class?

It is not known to cause disease in people and is widely used in schools. Normal hygiene still applies: move it with a spatula rather than fingers, wash hands after the lesson and dispose of old cultures with the school’s biological waste.

Last Updated: September 2026