Domain: Natural Science — Biochemistry & Molecular Biology
Target concept: When a small-molecule inhibitor is added, the lysozyme reaction slows down.

Video generation prompt: On the lab bench, two transparent beakers each contained the same turbid, cloudy bacterial-cell-wall suspension mixed with lysozyme enzyme; a triacetylchitotriose inhibitor solution was added only to the beaker on the right, which was labeled with a blue sticker, and the beakers were filmed side by side.

Evaluation guide:
(i) Target concept: Enzyme inhibition of lysozyme's peptidoglycan-hydrolyzing (cell-wall-lysing) activity by a small-molecule competitive inhibitor, triacetylchitotriose, which occupies lysozyme's substrate-binding cleft and blocks the natural bacterial-cell-wall substrate from binding, slowing the loss of turbidity that lysozyme activity would otherwise produce.
Minimum mechanism: Lysozyme must be active in both beakers' turbid bacterial suspension at the start; triacetylchitotriose must be present *only* in the right beaker and must competitively block the enzyme's active site, preventing peptidoglycan hydrolysis and thereby slowing the clearing (de-turbidification) reaction in that beaker only.
(ii) Storyline: Frame 1-2: Static wide shot showing two identical transparent beakers on a lab bench, both filled with the same cloudy, whitish bacterial suspension. Frame 3-4: Close-up action showing inhibitor solution delivered *exclusively* to the right beaker (e.g., dropper tip above right beaker, liquid stream entering only the right beaker). Frame 5-10: Return to a side-by-side static shot; the left beaker progressively clears as its turbidity drops, while the right beaker remains visibly cloudy, with the contrast persisting until the video ends. Viewpoint is fixed, front-facing, eye-level, with no camera movement or zoom.

Manual:
Experimental Procedure
1. Place two identical transparent glass beakers side-by-side on a lab bench.
2. Fill both beakers with equal volumes of a turbid bacterial-cell-wall suspension mixed with lysozyme enzyme.
3. Add triacetylchitotriose inhibitor solution to the right beaker only; label it with a blue sticker.
4. Observe turbidity change over time.
Observation of Experimental Phenomena
The left beaker progressively clears (its cloudy suspension becomes visibly transparent); the right beaker remains cloudy/turbid.
Summary of Experimental Principles
Triacetylchitotriose acts as a small-molecule competitive inhibitor of lysozyme, occupying its substrate-binding cleft and blocking access to the peptidoglycan substrate — thus slowing the enzyme's cell-wall-lysing (clearing) activity in the right beaker.

Prompt Grounding rubric:
level_1: The scene fails the basic setup: only one beaker appears instead of two, or the two beakers are stacked or spaced far apart rather than positioned next to each other on a lab bench; the right beaker carries no blue sticker; no inhibitor solution is shown or implied entering the right beaker; or the beakers are not filled with a matching turbid, cloudy liquid.
level_2: Two containers appear, but they are not both clearly transparent beakers, or one beaker's contents are missing; the blue sticker is absent from the right beaker, misplaced, or duplicated on the left beaker; the inhibitor is shown added to both beakers, to the left beaker, or its target is ambiguous; or the lab-bench setting is unclear (e.g., background looks unidentifiable).
level_3: Two transparent beakers sit next to each other on a lab bench, both filled with visually matching turbid, whitish bacterial suspension; the right beaker bears a blue sticker; a dropper or pipette adds inhibitor solution exclusively into the right beaker while the left beaker receives no addition.
level_4: All elements of 3-score are satisfied, AND the inhibitor-addition action completes before any turbidity change begins (addition and clearing never appear in the same moment); both beakers show identical starting turbidity; the blue sticker sits flush against the right beaker's outer wall, not floating or duplicated, and never appears on the left beaker.
level_5: All elements of 4-score are satisfied, AND the blue sticker remains attached to the right beaker for the entire video with no occlusion, flicker, or shift in position; the inhibitor stream is shown flowing continuously from a visible dropper or vessel into the right beaker with no jump cuts; no unrelated objects (stray gloves, extra pipettes, etc.) enter the frame during the addition sequence.

Scientific and Causal Correctness rubric:
level_1: Neither beaker's turbidity changes at all; or both beakers clear at the same rate with no distinguishable difference; or only the right (inhibitor-treated) beaker clears while the left stays turbid; or the suspension's color shifts to something other than cloudy-white-to-clear (e.g., turns brown, blue, or pink).
level_2: Both beakers eventually clear, but the right beaker clears first or faster than the left, reversing the expected relationship; or the two beakers show comparable turbidity throughout with no clear contrast; or the left beaker's clearing visibly begins before the inhibitor-addition step into the right beaker has finished.
level_3: The left (no-inhibitor) beaker's suspension progressively clears, visibly less cloudy over time, while the right (inhibitor-treated) beaker stays turbid or clears distinctly more slowly; the contrast in clarity between the two beakers is easy to see; the left beaker's clearing begins only after the addition step is complete.
level_4: All elements of 3-score are satisfied, AND the left beaker's clearing proceeds smoothly and continuously with no sudden re-clouding; the right beaker's cloudiness stays essentially unchanged throughout (no partial or intermittent clearing); neither beaker develops an unrelated color tint (e.g., yellowing or graying) alongside its turbidity change.
level_5: All elements of 4-score are satisfied, AND the left beaker ends the video visibly transparent, matching a fully cleared suspension, while the right beaker's suspension stays uniformly cloudy with no visible settling into a sediment layer or surface film that would misrepresent ordinary lysozyme clearing.

Spatiotemporal Consistency rubric:
level_1: A beaker's position on the bench changes abruptly between consecutive frames with no continuous motion connecting the two positions; the blue sticker or the inhibitor container appears or disappears from one frame to the next with no visible placement or removal action; the overall scene brightness switches abruptly between bright and dark partway through the video; or the rim of a beaker or the liquid's surface visibly fractures or tears apart.
level_2: A beaker drifts sideways or wobbles noticeably across frames even though nothing should be moving it; the blue sticker or one of the beakers is hidden from view for two or more consecutive frames; the whole frame suddenly washes out or darkens for a moment; or heavy motion blur makes it hard to tell which beaker is which or where the sticker sits.
level_3: Neither beaker changes position, tilts, or disappears at any point; the blue sticker stays fixed on the same spot on the right beaker in every frame; the turbid liquid's surface stays visually still or settles gently, without sudden sloshing or freezing into an unnaturally rigid shape; the camera framing, angle, and apparent light source stay the same from the first frame to the last.
level_4: All elements of 3-score are satisfied, AND the blue sticker's color and each beaker's transparency stay constant frame to frame with no flicker; the liquid's meniscus in each beaker stays a single continuous curve without distorting or splitting; neither beaker's outline stretches, warps, or skews out of its cylindrical shape; no frame appears to repeat or double as a stutter.
level_5: All elements of 4-score are satisfied, AND all motion (liquid settling, minor surface ripple) looks smooth and continuous with no abrupt jump or freeze; the outlines of both beakers and the visible boundary between clear and turbid liquid remain steady and sharp throughout, without flickering or shimmering.