Domain: Healthcare — Digestive Physiology
Target concept: Downloaded table(s)

Video generation prompt: Two test tubes are placed side by side on the table. The left test tube contains a suitable amount of vegetable oil, while the right test tube contains an equal volume of the same vegetable oil. An appropriate amount of pancreatic lipase and colipase is added to the left test tube, whereas only an equivalent amount of pancreatic lipase is added to the right test tube. Both test tubes are incubated at 37°C for 60 minutes. The image focuses on the emulsified state of the contents in both test tubes.

Evaluation guide:
(i) Target concept: Colipase-dependent enzymatic emulsification of dietary triglycerides by pancreatic lipase.
Minimum mechanism: Colipase anchors pancreatic lipase at the oil-water interface and enables it to hydrolyze the vegetable oil's triglycerides; the resulting fatty acids and monoglycerides act as surfactants that keep the oil dispersed as a fine emulsion. Without colipase, pancreatic lipase cannot sustain productive binding to the interface, so hydrolysis stays minimal and essentially no emulsifying surfactants accumulate over the 60-minute incubation. The tube without colipase therefore remains phase-separated (a clear oil layer over the aqueous layer) rather than forming a stable emulsion.
(ii)Storyline: [Frame 0–2] Static wide shot: two identical upright glass tubes side-by-side, filled to matching meniscus heights with pale yellow oil. [Frame 3–4] Left tube receives one coordinated addition (a two-part or dual-colored droplet/dropper) representing lipase+colipase; right tube receives a separate, single addition (one differently marked droplet/dropper) representing lipase only. [Frame 5–10] The shot holds static: the left tube develops and maintains a uniformly cloudy, turbid appearance (fine emulsion); the right tube develops and maintains a sharp phase separation, with a clear oil layer sitting over the aqueous layer and no emulsification. Viewpoint is fixed frontal, shallow depth-of-field emphasizing tube contents; lighting is diffuse with a gentle directional highlight to reveal surface state; no motion occurs except each initial droplet's descent; all causal links stay visually anchored to each tube's specific reagent input.

Manual:
Experimental Procedure
1. Place two identical glass test tubes side-by-side on a lab table.
2. Fill both with equal volumes of pale yellow vegetable oil (meniscus height matched).
3. Add pancreatic lipase + colipase to left tube; add pancreatic lipase only to right tube.
4. Incubate both at 37°C for 60 min (implied by a static, unchanging frame held after the additions, with no camera cut, pan, or continued handling).
Observation of Experimental Phenomena
Left tube (lipase + colipase): develops a uniformly cloudy, milky appearance with no distinct oil layer, consistent with a stable, finely dispersed emulsion. Right tube (lipase only): remains phase-separated into a clear upper oil layer and a lower aqueous layer, with no emulsification, because lipase cannot sustain productive interfacial binding without colipase.
Summary of Experimental Principles
Colipase binds pancreatic lipase and anchors it at the oil-water interface, enabling sustained hydrolysis of the vegetable oil's triglycerides; the resulting fatty acids and monoglycerides act as surfactants that keep the oil dispersed as fine droplets (an emulsion). Without colipase, lipase cannot maintain productive contact with the interface, so hydrolysis stays minimal and essentially no surfactant accumulates over the 60-minute incubation — the tube therefore stays phase-separated rather than forming an emulsion.

Prompt Grounding rubric:
level_1: No two test tubes are visible, or only one appears; or no pale yellow vegetable oil is visible in either tube; or the two reagent additions are not visually distinguished from each other (e.g., identical droppers/colors added to both tubes with nothing marking one as 'lipase + colipase' and the other as 'lipase only'); or the tubes are not placed side-by-side on a flat surface.
level_2: Two test tubes stand side-by-side and both contain visible pale yellow vegetable oil, but at least one of the following is missing: (a) a clearly distinct addition event for each tube (e.g., the left tube's dropper/droplet differs in color, label, or count from the right tube's), so a viewer cannot tell that the left tube received lipase+colipase while the right received lipase alone; (b) any cue that the 37°C/60-minute incubation occurred, i.e., the shot cuts away, pans, or shows continued handling/motion in the tubes immediately after the additions, with no subsequent held, unchanging frame, no 37°C label, no timer, and no warm-ambient tint; (c) visibly equal oil volume: the meniscus heights are clearly mismatched, or one tube is visibly over- or under-filled relative to the other.
level_3: Two test tubes stand side-by-side on the table, filled to matching meniscus heights with pale yellow vegetable oil; the left tube receives a visually distinct addition from the right (e.g., a two-part or dual-colored droplet/dropper for 'lipase + colipase' into the left tube versus a single, differently marked droplet/dropper for 'lipase only' into the right); once both additions are complete, the shot holds on a stable, unchanging frame for the remainder of the clip (with no cut, pan, or continued handling), and this static hold alone is enough to imply that the 37°C, 60-minute incubation has taken place; an explicit label, timer, or warm tint is not required to earn this level.
level_4: Everything required for the 3-point level is present, and in addition: the left tube's addition is shown as two visually separable reagent inputs (e.g., two differently colored droplets, or a dropper explicitly marked 'lipase + colipase') while the right tube's addition is shown as a single reagent input (one droplet or one dropper marked 'lipase only'); no extraneous props appear on the table (no third tube, no stray pipette tips, no inconsistent glove use); and the camera holds a fixed frontal framing throughout, without panning, tilting, or zooming.
level_5: Everything required for the 4-point level is present, and in addition: both tubes stay fully inside the frame at every moment, with no cropping; every reagent addition lands inside the tube mouth with no visible splashing outside the tube and no droplet lingering in mid-air past its initial drop; there is no ambiguity about reagent count: exactly two distinguishable additions in the left tube and exactly one in the right; the background is plain and uncluttered so it does not compete with the tube comparison; and the lighting is even enough that the oil surface (turbid or clear) stays legible in both tubes without glare washing it out.

Scientific and Causal Correctness rubric:
level_1: No visible difference in cloudiness between the two tubes: both look equally clear or equally turbid; or the tubes show an outcome inconsistent with the chemistry entirely, such as the oil appearing solidified, brightly colored, or foamed in either tube.
level_2: A difference in appearance is visible, but it points the wrong way or is not tied to the reagent additions: e.g., the right (lipase-only) tube looks distinctly more turbid/emulsified than the left (lipase+colipase) tube; or only one tube shows any change while the other looks unchanged from before the additions were made; or the turbidity/separation is already visible before the additions occur.
level_3: The left tube (lipase + colipase) looks visibly cloudy/turbid, consistent with a fine, stable oil-in-water emulsion forming there; the right tube (lipase only) looks visibly separated into a clear oil layer sitting over an aqueous layer, showing no emulsification; both appearances hold steady once established, with no active mixing motion visible during the observed period.
level_4: In addition to the 3-point requirements, the contrast between the two tubes is unambiguous: the left tube's turbidity is fairly even across the whole liquid column rather than confined to one region; the right tube shows a clean, distinct interface between the oil layer and the aqueous layer with no haze or suspended droplets. Neither tube's appearance can be explained by an artifact such as dust, bubbles, or condensation on the glass rather than by the reagents added.
level_5: In addition to the 4-point requirements, the timing is clean: the left tube's turbidity only becomes visible after its two-part addition and holds steady afterward; the right tube's clear phase separation only becomes visible after its single-reagent addition and holds steady afterward, with no residual turbidity or suspended oil droplets in either of its layers; and neither tube shows unrelated visual noise (stray particles, streaks, or an irregular meniscus) that would confuse which tube is which.

Spatiotemporal Consistency rubric:
level_1: Severe continuity break: the test tubes jump to a different position or size between one frame and the next; the oil's fill level in a tube changes suddenly without a visible cause; the room lighting flashes, flickers, or the tube shadows swap sides abruptly; or a reagent droplet appears already inside a tube with no visible drop or fall beforehand.
level_2: A moderate continuity break: (a) one or both tubes vanish behind an occluding object, or drop out of frame, for more than a moment and then reappear; (b) a reagent droplet's path into a tube skips: it is visible near the tube rim in one frame and already fully inside on the next, with no continuous fall in between; (c) the oil meniscus in a tube rises or falls between frames with no addition or other visible cause; (d) background objects (e.g., the tabletop edge, wall) visibly warp or shear from one frame to the next.
level_3: Both test tubes hold a constant position, size, and upright orientation throughout; neither tube disappears or reappears without a clear, visible cause (such as something briefly passing in front of it); each reagent addition shows a continuous, visible fall into its tube rather than skipping into place; once settled, the oil level in each tube stays constant; and the direction and brightness of the light on the tubes stays the same across the clip, so their cast shadows do not swap sides or change strength.
level_4: In addition to the 3-point requirements, both tubes stay rigidly still with no wobble or tremor; the oil surface in each tube keeps a natural curved meniscus against the glass rather than looking flat or jagged; the emulsified or layered state of each tube's contents stays visually legible in every frame of the observation period, without blur or ghosting smearing it away; and the camera keeps a constant frontal framing with no perspective shift between the two tubes.
level_5: In addition to the 4-point requirements, the clip plays with no stutters, skipped frames, or visible frame-repeats; light reflecting off the liquid surfaces behaves consistently, with no sudden highlight jump unrelated to any change in the lighting; the glass walls of both tubes keep a consistent, even thickness and clarity with no warping; and the side-by-side spacing between the two tubes stays visually constant and parallel throughout, without one tube appearing to drift closer or farther than the other.