Domain: Natural Science — Biochemistry & Molecular Biology
Target concept: A simple laboratory demonstration: Fluorescent RNA products accumulate gradually in a test tube over time

Video generation prompt: On an experimental bench, two test tubes with blue and red caps are present; a gloved hand adds DNA template, nucleotides, and RNA polymerase to the blue-capped tube, after which both tubes are placed under ultraviolet light.

Evaluation guide:
(i) Target concept: In vitro transcription-dependent fluorescent signal generation requires all three core reagents (DNA template, nucleotides, RNA polymerase) to be co-localized in a single reaction vessel; fluorescence is contingent on both successful enzymatic synthesis and subsequent UV excitation.
Minimum mechanism: RNA polymerase must bind DNA template and catalyze phosphodiester bond formation using nucleotides to produce RNA; fluorescent signal arises only from RNA-dye complexes (not free dye or reagents alone); UV illumination is necessary but insufficient without RNA product.
(ii)Storyline: Frame 1–3: Static side-by-side view of blue-capped and red-capped tubes on bench. Frame 4–6: Gloved hand enters frame, retrieves reagents, and delivers them exclusively into blue-capped tube (no contact with red tube). Frame 7–8: Both tubes remain stationary and unmoved. Frame 9–10: UV light activates: immediate onset of fluorescence exclusively in blue-capped tube, with visible progressive brightening; red-capped tube shows zero emission. All events occur from fixed frontal bench-level viewpoint; no camera movement; no occlusion of tubes or hand during critical actions.

Manual:
Experimental Procedure
1. Place two upright test tubes side-by-side on bench: left tube has blue cap, right tube has red cap.
2. Using gloved hand, add DNA template, nucleotides, and RNA polymerase exclusively to blue-capped tube.
3. Place both tubes under ultraviolet light.
Observation of Experimental Phenomena
Under UV light, only the blue-capped tube emits visible fluorescence; the red-capped tube remains non-fluorescent. Fluorescence appears gradually and intensifies over time within the blue-capped tube.
Summary of Experimental Principles
Fluorescent RNA products form only when transcription occurs: DNA template + nucleotides + RNA polymerase enable RNA synthesis. RNA binds fluorescent dye (inherent or co-administered), causing UV-induced fluorescence. No transcription components in red-capped tube → no RNA → no fluorescence.

Prompt Grounding rubric:
level_1: No test tubes visible, or no blue/red caps present; no gloved hand shown; no DNA template, nucleotides, or RNA polymerase added; no ultraviolet light illumination; none of the required objects or actions from the posted_prompt appear.
level_2: At least one test tube is visible with a cap, but cap colors are incorrect (e.g., both blue, both red, or neither blue nor red); OR gloved hand appears but performs no addition action; OR UV light is present but no tubes are placed under it; OR ≥1 required object (DNA template, nucleotides, RNA polymerase) is depicted but not associated with the blue-capped tube.
level_3: Two test tubes are present with correctly colored blue and red caps; a gloved hand adds material to the blue-capped tube only; both tubes are placed under UV light; all required objects (DNA template, nucleotides, RNA polymerase) are visually present and unambiguously associated with the blue-capped tube during addition; no extraneous additions to the red-capped tube.
level_4: All conditions for score 3 are satisfied, AND the blue-capped tube is the only tube receiving reagents (no contact between gloved hand and red-capped tube during addition phase); AND both tubes remain in fixed side-by-side spatial relationship throughout; AND UV illumination is applied simultaneously to both tubes after addition (no sequential or partial illumination).
level_5: All conditions for score 4 are satisfied, AND the gloved hand clearly releases reagents into the blue-capped tube (not hovering, not touching cap, not spilling outside); AND the red-capped tube remains completely untouched by the hand at all times; AND both tubes are identically positioned (same orientation, same height, same foreground/background alignment) before and during UV exposure; AND no object occludes either tube or the hand during any frame.

Scientific and Causal Correctness rubric:
level_1: No fluorescence observed in either tube under UV light; OR fluorescence appears in red-capped tube only; OR fluorescence appears before addition or without UV illumination; OR fluorescence is static and identical in both tubes with no differential accumulation.
level_2: Fluorescence appears in at least one tube under UV light, but not in the way the setup implies: for example it appears at the same time and with matching intensity in both tubes, or it shows up in the red-capped tube even though no reagents were ever added there, or it appears in the blue-capped tube before any reagent has actually been added or before the tubes are placed under UV light.
level_3: Fluorescence appears exclusively in the blue-capped tube under UV light; fluorescence is absent in red-capped tube under UV light; fluorescence emerges only after reagent addition and only during UV illumination; fluorescence is visually distinguishable as a glow (not reflection or glare) and localized inside the blue-capped tube.
level_4: Beyond the exclusive, reagent-dependent, UV-triggered glow required for score 3, fluorescence in the blue-capped tube increases visibly over time (at least two discernible intensity states: low to higher) while the red-capped tube remains non-fluorescent throughout; and no fluorescence appears in solution outside the tube or on the cap or hand.
level_5: Beyond the progressive brightening and spatial containment required for score 4, fluorescence originates solely from the liquid volume inside the blue-capped tube (not the cap, not the meniscus edge, not the tube wall); the red-capped tube shows no emission whatsoever (no faint glow, no halo, no residual luminescence, even briefly) under identical UV illumination; and fluorescence onset strictly follows completion of the reagent addition and precedes or coincides with UV activation (no glow visible before the UV light turns on).

Spatiotemporal Consistency rubric:
level_1: Test tubes teleport between frames; cap colors change mid-sequence; hand disappears/reappears without motion continuity; UV light flickers on/off erratically; tube contents deform discontinuously (e.g., sudden volume shift, phantom meniscus); spatial layout collapses (e.g., side-by-side becomes stacked then side-by-side again).
level_2: At least one major spatiotemporal break: e.g., hand moves toward blue tube but reagent addition occurs off-screen; UV light turns on while tubes are out-of-frame then reappear illuminated; one tube rotates or shifts position abruptly between addition and UV phases; shadow direction flips inconsistently across frames.
level_3: All objects maintain consistent spatial relationships: blue and red tubes remain side-by-side at fixed relative positions; gloved hand moves continuously from reagent source to blue tube mouth; no object vanishes or jumps; lighting (ambient + UV) remains stable in direction and intensity; no structural distortion (e.g., tube curvature, cap fit, glove texture) changes unnaturally.
level_4: All conditions for score 3 are satisfied, AND motion is smooth and physically plausible: hand trajectory is unbroken and terminates precisely at blue tube opening; tube placement under UV light occurs via continuous lateral translation (not cut/paste); no inter-frame strobing, warping, or micro-jitter in tube geometry or hand posture.
level_5: All conditions for score 4 are satisfied, AND every frame preserves rigid-body coherence: tube walls remain straight and parallel; cap-tube interface shows no interpenetration or misalignment; glove fingers retain consistent bending state during motion; UV illumination produces uniform glow distribution within blue tube with no frame-to-frame intensity pulsing or spatial jumping of emission region.