The sodium ion looked shocked. It had been going the wrong way, against the current. But the pump didn't care. It cracked another ATP. Heave . Another ion. Heave . Against the flow. Uphill. Spending energy like a miser spends gold.
It was the smell that hit Jamie first. Not the sterile, clinical scent of a hospital, but the sweet, cloying perfume of the biology lab: preservative, agar, and the faint ghost of a dissected frog from third period. explanation of active transport
Then the weird thing happened. The room didn't change, but Jamie’s attention did. It was like those magic-eye posters from the dentist’s office—if you stared long enough, the hidden shape popped into focus. The sodium ion looked shocked
