The Drug Did Not Make Them Resistant

You'll learnthat resistant cells exist before the antibiotic — mutation and selection are separate events.

A patient takes an antibiotic, and within days the infection is mostly resistant bacteria. It looks like the drug taught the cells a trick — but the resistant cells were in the dish before the bottle was opened. Twelve short steps; press Next for each one.

AP BIOLOGY · 12 STEPS · 6 QUICK CHECKS · 4 RESISTANT CELLS BEFORE THE DRUG · DRUG = FILTER, NOT FACTORY · v5

100 cells · variation first · drug second

Before you start

What you're looking at

A dish of 100 bacterial cells at generation 0: 96 susceptible, 4 already resistant, and no antibiotic anywhere.

The question

Did the drug create the resistant cells, or were they already there?

Step 1 / 12