Domain: Engineering — Agricultural Engineering
Target concept: Observing the dent maize kernels, it was confirmed that the embryo is pale yellow, accounting for approximately one-third of the kernel, and the kernel shape is dent-type.

Video generation prompt: Place a few dent corn kernels on a tray. Select one kernel and rotate it to show its front and side surfaces. Cut the kernel longitudinally to expose its internal structure. Demonstrate the position and proportion of the embryo, and display the morphological type of the kernel through rotation.

Evaluation guide:
(i) Target concept: Visual verification of dent-type maize kernel morphology and embryo anatomy via controlled manipulation and sectioning.
Minimum mechanism: Kernel must be biologically intact, dry, and mature; rotation must preserve rigid-body motion; cut must be planar and longitudinal to reveal true internal cross-section; embryo color and proportion must derive from natural maize biochemistry (carotenoid-rich but low-intensity pigmentation) and developmental geometry.
(ii)Storyline: [Phase 1] Static shot: tray with multiple dent corn kernels in view. [Phase 2] Focus shift + selection: one kernel isolated and lifted onto neutral background. [Phase 3] Controlled rotation: kernel rotated smoothly ~180° to reveal front (dent visible) and side (curved, tapered) profiles; viewpoint fixed, no zoom. [Phase 4] Stabilization & cut: kernel held still; knife approaches and bisects longitudinally in one motion; cut plane aligns with kernel symmetry axis. [Phase 5] Post-cut rotation: cut kernel rotated to expose interior; embryo appears pale yellow, contiguous, and occupies roughly one-third of the kernel's length in the cut face, at the basal end, all visible without annotation or zoom.

Manual:
Experimental Procedure
1. Place 3–5 dry dent corn kernels on a neutral-toned tray.
2. Select one kernel and rotate it slowly to display front (crown with dent) and side (asymmetric curvature) surfaces.
3. Hold kernel steady and make a single clean longitudinal cut from crown to base.
4. Rotate cut kernel to expose interior and highlight embryo location and proportion.
Observation of Experimental Phenomena
- Kernel exhibits characteristic dent-type shape: visible indentation at crown and lateral asymmetry.
- After longitudinal cut, embryo appears as a contiguous pale yellow region occupying roughly one-third of the kernel's length in the longitudinal cut face, located at the basal end adjacent to scutellum.
Summary of Experimental Principles
- Dent maize kernels have a morphologically distinct crown indentation and asymmetric shape.
- Embryo is pale yellow and occupies approximately one-third of the kernel's length as seen in a longitudinal cut, consistent with its role as the germinative tissue embedded within the starchy endosperm.

Prompt Grounding rubric:
level_1: No dent corn kernels are visible anywhere in the shot; or no tray is shown; or no kernel is ever rotated; or no longitudinal cut is made; or the kernel's interior is never shown at all.
level_2: Dent corn kernels sit on a tray, but no single kernel is picked out and handled on its own; the camera never turns a kernel to show its front and side; no longitudinal cut is made; nothing about where the embryo sits or what the kernel's dent shape looks like is ever demonstrated.
level_3: A few dent corn kernels rest on a tray; one kernel is picked up and rotated enough to show both its front (crown) face and a side profile; however, that kernel is never cut open, so no internal structure is shown.
level_4: Everything at the 3-point level holds, and in addition: a longitudinal cut is made through the very same kernel that was rotated, and the cut opens it enough to reveal the interior; a paler region distinct from the surrounding starchy interior is visible somewhere on the cut face (without needing to judge its exact color or size here); however the dent-type crown indentation is not clearly re-confirmed by rotating the cut kernel afterward, or the cut face is partly angled away from the camera or partly blocked by the knife or fingers.
level_5: Everything at the 4-point level holds, and in addition: the cut face is fully unobstructed and faces the camera directly, so the whole interior cross-section (including the paler embryo region) is clearly visible with nothing hidden by fingers, tools, or camera angle; the same kernel is rotated both before and after cutting, so its crown indentation and asymmetric side profile are shown continuously on camera from selection through the final cut.

Scientific and Causal Correctness rubric:
level_1: The kernel shown is not dent-type (e.g., it looks round, flint, or floury instead); or there is no embryo visible at all, or it is the wrong color (white, brown, translucent), or it visibly takes up less than about a quarter or more than half of the kernel; or the cutting action and the embryo's appearance have no visible connection to each other.
level_2: The kernel's shape doesn't match dent corn (it looks symmetric, blunt-ended, or evenly rounded rather than dented and asymmetric); the embryo is present but the wrong color (dark yellow, orange, or beige instead of pale yellow); its size is clearly off (a tiny speck, or over half the kernel); the cut fails to show where the embryo sits, or it doesn't reveal any internal layering at all.
level_3: The kernel shows dent-type morphology (a visible indentation on the crown, an asymmetric overall shape); the embryo is present and pale yellow; it occupies roughly one-third of the kernel, visible as a distinct, contiguous pale region next to the dent; however, the embryo's position is not correctly oriented (e.g., it appears near the tip rather than the base) or its relation to the surrounding endosperm is unclear.
level_4: Everything at the 3-point level holds, and in addition: the kernel shows a clear crown indentation and asymmetric curvature typical of dent corn; the embryo is pale yellow and contiguous, occupying roughly one-third of the kernel's length in the cut face; it sits at the basal end near the hilum, next to the scutellum, surrounded by the starchy endosperm, consistent with the rotation showing the shape and the cut then revealing this interior.
level_5: Everything at the 4-point level holds, and in addition: the dent-type crown indentation and lateral asymmetry are unmistakable; the embryo is pale yellow, contiguous, and occupies about one-third of the kernel's length in the longitudinal cut face, positioned basally next to the scutellum, with the embryonic axis visible within it; nothing in the image contradicts real maize kernel anatomy, and each step (rotation, cut, exposure) visibly leads into the next.

Spatiotemporal Consistency rubric:
level_1: The tray or a kernel jumps to a new position between frames with no motion shown in between; the selected kernel's rotation jumps, freezes, or reverses direction abruptly; the cutting motion appears with no hand or knife ever shown moving into position; the room's lighting changes suddenly from one frame to the next; the kernel visibly bends or squashes out of its rigid shape during rotation or cutting.
level_2: The kernel's rotation is choppy: it stutters, skips, or pauses noticeably before continuing; the knife starts cutting before the kernel has stopped moving or settled in place; the kernel seems to disappear during the cut and then reappear already sliced; a shadow or highlight on the kernel jumps to an inconsistent position relative to the tray or knife.
level_3: The kernel's rotation plays out as one continuous turn from a fixed camera angle; the cut is made on the very same kernel that was just rotated; the tray does not shift position; the kernel's size, orientation, and shading stay consistent throughout; there is a small amount of jitter during the rotation, or the knife's first contact is a little off from the kernel's centerline, but nothing else is wrong.
level_4: Everything at the 3-point level holds, and in addition: the rotation turns at a steady, unbroken pace with no slipping or wobble; the knife follows a natural hand motion into the kernel along its long axis; the kernel itself stays rigid and does not deform; the lighting, shadows, and any reflections on the kernel's surface stay consistent with a single fixed light source and camera angle; nothing overlaps or layers incorrectly, e.g., the knife never appears to pass through the tray.
level_5: Everything at the 4-point level holds, and in addition: the rotation keeps a constant speed with no drift in perspective; the cut is a single smooth stroke that enters and exits along the kernel's natural longitudinal axis; the kernel keeps the same size, surface texture, and shading across every phase: on the tray, during rotation, during cutting, and after the cut; the tray, kernel, and knife keep sensible relative positions and sizes to one another throughout; the overall motion looks fluid, with no stutter or rubbery, warped-looking movement at any point.