Prompt Description

I. Overall Layout and Narrative Flow: Employ a "left-to-right, top-to-bottom" Z-shaped narrative flow, integrating the entire process into a single scene to avoid partitioning. Starting Point (Top Left): Cholesterol molecule enters the mitochondrion. Core Effect (Middle Left): Cholesterol embeds in the inner membrane, altering its physical properties (increased order, decreased fluidity, decreased permeability). Structural Representation (Bottom Left/Middle Bottom): Show the "stable" inner membrane structure resulting from the cholesterol. Functional Outcome (Middle Right): Oxidative phosphorylation proceeds efficiently on the stable inner membrane, producing a large amount of ATP. Final Conclusion (Bottom Right): Summary diagram (Cholesterol ↑ → ATP ↑). II. Detailed Drawing Steps: Phase 1: Cholesterol Input and Inner Membrane Localization (Top Left Area) Draw a cross-section of a mitochondrion, highlighting the structure of its inner membrane and cristae. Above the mitochondrion, draw several yellow dots (representing cholesterol molecules, color value #F1C40F) moving towards the inner membrane. Use arrows to indicate cholesterol embedding into the phospholipid bilayer of the inner membrane. Phase 2: Effect of Cholesterol on Membrane Physical Properties (Middle Left Area) Inner Membrane Local Magnification A (Order and Fluidity): Draw a magnified box around the cholesterol embedding site. Within the box, draw two small segments of the phospholipid bilayer for comparison: Upper Segment (Without Cholesterol): Phospholipid molecules (light blue thin ovals, #D6EAF8) are arranged relatively loosely, with curved wavy arrows passing through to indicate "high fluidity." Lower Segment (With Cholesterol): Yellow dots (cholesterol) are inserted between phospholipid molecules. The molecular arrangement becomes tight and orderly, with straight, obstructed arrows indicating "low fluidity (increased order).". Side note key conclusion: "Cholesterol ↑ → Lipid Order ↑ → Fluidity ↓". Inner Membrane Local Magnification B (Permeability): To the right of magnification A, draw another magnified box showing a cross-section of the inner membrane. Draw a simplified proton pump on the membrane (such as Complex IV, represented by a purple square, #8E44AD). Pump Function: Pumps a red "H⁺" from the matrix side (bottom) to the intermembrane space (top). Membrane Properties: Draw small, thin red dashed arrows on the membrane to indicate a small amount of proton leakage (low permeability). Side note: "Cholesterol ↑ → H⁺ Permeability ↓". Label "High H⁺ concentration" on the intermembrane space side and "Low H⁺ concentration" on the matrix side to establish the concept of a gradient. Phase 3: Presentation of Stable Inner Membrane Structure (Bottom Left/Middle Bottom Area) Direct the view back to the complete mitochondrion. Outline the contours of the inner membrane and cristae with bold, smooth, continuous lines, and add shields or solid icons next to them, labeled: "Enhanced Physical Stability". Summarize in a formula box next to the diagram: "Fluidity ↓ + Permeability ↓ → Inner Membrane Stability ↑". Phase 4: Efficient ATP Synthesis (Middle Right Area) Show the enzyme activity platform: On the stable inner membrane (especially the cristae membrane), draw a simplified respiratory chain supercomplex (which can be simplified into a connected blue-purple-red block group, labeled "Respiratory Chain Complex") and ATP synthase (orange mushroom-shaped structure, #E67E22).