Domain: Healthcare — Basic Immunology
Target concept: The latex agglutination reaction is caused by antigen-antibody binding.

Video generation prompt: On the experimental bench, two petri dishes contain latex beads coated with antigen; a gloved hand uses a pipette with a red tip to add liquid to the left side and a pipette with a blue tip to add liquid to the right side, then gently agitates both.

Evaluation guide:
(i) Target concept: Antigen-antibody mediated crosslinking of antibody-coated latex beads leading to macroscopic agglutination.
Minimum mechanism: Added liquid must contain antibodies complementary to the antigen on beads; binding must be multivalent to enable lattice formation; physical agitation must be sufficient to promote collision but insufficient to break specific bonds.
(ii)Storyline: Frame 0–2: Static wide shot showing two side-by-side petri dishes with evenly dispersed latex beads; gloved hand enters frame holding two pipettes (red tip left, blue tip right). Frame 3–4: Red pipette dispenses liquid into left dish; blue pipette dispenses into right dish: both actions occur sequentially or simultaneously with clear spatial separation. Frame 5–7: Hand transitions to agitation motion: fingertip or pipette gently swirls liquid in both dishes, maintaining side-by-side visibility. Frame 8–10: Beads in both dishes visibly transition from uniform dispersion to clustered aggregates; clusters persist through agitation without full redispersion; no clumping observed before liquid contact; viewpoint remains fixed frontal-overhead, no occlusion of dish interiors during key events.

Manual:
Experimental Procedure
1. Place two petri dishes side-by-side on bench.
2. Ensure both contain visible latex beads coated with antigen.
3. Using red-tipped pipette, add liquid to left dish.
4. Using blue-tipped pipette, add liquid to right dish.
5. Gently agitate both dishes.
Observation of Experimental Phenomena
Latex beads in both dishes form visible clumps (agglutination) after liquid addition; clumps are irregular aggregates larger than individual beads; no clumping occurs before addition.
Summary of Experimental Principles
Latex agglutination reaction is caused by antigen-antibody binding.

Prompt Grounding rubric:
level_1: The scene shows no petri dishes at all, or shows dishes with no latex beads inside; no gloved hand and no pipette with a colored tip appears; nothing in the frame resembles liquid being added or a swirling/agitating motion; the setting does not read as a lab-bench experiment.
level_2: Petri dishes appear but are empty of beads, or a bead-filled dish appears alone rather than as a pair; the pipette tips are uncolored, or only one pipette is shown; the hand adding liquid is bare rather than gloved; agitation never happens in one or both dishes; at least three of these setup elements are missing or wrong.
level_3: Two petri dishes sit on the bench, each holding visible latex beads; a gloved hand appears; a red-tipped pipette adds liquid to one dish and a blue-tipped pipette adds liquid to the other; both dishes are then gently swirled; every element from the prompt is present, even if the two dishes are not perfectly aligned side by side or the swirling on one dish clearly lags the other.
level_4: Everything required for a 3 also holds, and additionally: the red-tipped pipette adds its liquid specifically to the left dish and the blue-tipped pipette to the right dish, never swapped; the two dishes sit side by side for the whole shot; liquid is added to both dishes before either one is swirled; no extra dish, spare pipette, or unrelated object appears in the shot.
level_5: Everything required for a 4 also holds, and additionally: both pipetting actions happen in one continuous shot with no cut or camera reset in between; the glove stays on the hand and the red/blue tip colors stay clearly readable throughout; the swirling motion looks like the same gesture repeated on each dish rather than two different techniques; nothing (glare, the hand itself, a shadow) blocks the view of either dish's beads at the moments liquid is added or swirled.

Scientific and Causal Correctness rubric:
level_1: Neither dish shows any clumping of beads after its liquid is added; the beads look the same before and after, evenly spread with no visible connection between the liquid added and any change in the beads.
level_2: Only one of the two dishes shows beads clumping while the other stays evenly dispersed; or clumps are already visible before the liquid touches the beads; or the beads change color, shrink, or dissolve instead of clustering together, none of which is how an antigen-antibody agglutination reaction looks.
level_3: After its respective liquid is added, each dish shows beads gathering into clumps clearly larger than a single bead, scattered unevenly rather than in a neat ring or pattern; the clumping in each dish only appears once its own liquid has been added, not before.
level_4: Everything required for a 3 also holds, and additionally: the clumps are visibly made of several beads stuck together (not a smear, stain, or dissolved patch); no dish shows a color change, foaming, or bead dissolution standing in for clumping; the timing in each dish stays tied to its own addition step: the left dish's clumps trace to the red-tipped pipette's liquid, the right dish's clumps trace to the blue-tipped pipette's liquid.
level_5: Everything required for a 4 also holds, and additionally: the clumps in both dishes look like irregular, multi-bead aggregates rather than uniform rings, crystals, or a single giant blob; individual beads outside a clump keep moving independently rather than all locking together at once; when the dishes are swirled, the clumps mostly hold together rather than fully breaking back into separated single beads, consistent with a real antigen-antibody bond rather than incidental clustering.

Spatiotemporal Consistency rubric:
level_1: A petri dish jumps to a new spot on the bench between shots with no hand or motion explaining the change; the gloved hand disappears mid-pipetting and reappears elsewhere; a pipette's position changes with no visible hand movement; the lighting abruptly swings between bright and dark with no light source or cause; beads flicker or warp into unnatural shapes instead of staying as distinct spheres; beads change from spread out to clumped with no liquid ever touching them.
level_2: One dish shifts sideways between shots while the other stays put; the hand's wrist bends in a way a real wrist can't during pipetting; a pipette tip's color changes partway through the dispensing action; the shadow cast by a dish or hand flips direction between frames with no matching light change; the swirling motion starts or stops abruptly instead of easing in and out; beads drift upward or sink as if floating in air rather than settling in liquid.
level_3: The two dishes stay in the same spot relative to each other and the bench for the whole sequence; the hand moves in one smooth path from dish to dish; each pipette keeps its own tip color and orientation throughout; the swirling motion is continuous, without freezing or snapping back; neither dish's shape nor the beads inside it warps or breaks apart on its own.
level_4: Everything required for a 3 also holds, and additionally: when the gloved hand passes over a dish it visibly blocks part of that dish rather than floating oddly in front of or behind it; the two dishes keep the same spacing and orientation to each other as the hand moves between them; the beads' transition from spread out, to clumping, to settled clusters happens gradually in both dishes rather than jumping straight from dispersed to clustered between two frames.
level_5: Everything required for a 4 also holds, and additionally: the hand's movement between the two dishes and the swirling motion in each one look like one continuous, evenly paced action rather than speeding up, pausing, or resetting; there is no visible flicker, ghost trailing, or smearing where the hand, pipette, or beads move fastest; a bead or clump that passes behind the pipette tip or the hand stays fully hidden rather than flickering in and out of view.