# Reserved new files · first response

Staff chooses one file after feedback and a delay. Learners use the assigned source/task only. Capture this first response before its matching later page. All numbers and descriptions are original conceptual models, not actual investigation results.


## E2 first

**Source:** Neutral J is 4 mmol/L outside and 1 mmol/L inside and can cross the bilayer. Neutral K is 2 mmol/L outside and 6 mmol/L inside; a specified ATP-coupled pump carries K inward. A separate pouch has 0.22 mol/L impermeant neutral solute both inside and outside; water can cross, solute cannot, and initial temperature/pressure are equal. The complete membrane word map has water on each side, phospholipid bilayer, selective channel, external carbohydrate on glycoprotein and cholesterol among tails in a typical animal model; no scale or full component inventory is given.

**Task:** Explain J and K's mechanisms, directions and energy statements with evidence and the meaning of net movement. Explain head/tail orientation and the three listed component roles with a model limit. Explain the pouch's initial net water result and continuing molecular motion under the supplied permeability, temperature and pressure conditions; name an unavailable outcome. Preserve first work before the later page.