Mistake Master
Student view — seeing the site as a student does
Mistake Master · AP Biology · Unit 6 · Step-Through Animation

Same Book, Different Pages

You'll learnwhy cells with identical genomes become different types by expressing different genes.

A neuron and a liver cell look nothing alike, behave nothing alike, and carry exactly the same DNA — the same complete genome, gene for gene. Watch the switches get thrown, then watch the two mistakes this topic exists to kill: that each cell type has its own gene set, and that specialising throws the unused genes away. Ten short steps; press Next for each one.

10 STEPS · 6 QUICK CHECKS · ONE GENOME IN EVERY SOMATIC CELL · SPECIALIZATION = DIFFERENTIAL EXPRESSION · OFF IS NOT GONE · v5

one genome in every cell · what differs is which genes get read
Before you start
What you're looking at
A single zygote dividing by mitosis into four cell types, each daughter showing the same row of six gene loci.
The question
If a muscle cell and a beta cell hold identical genes, why do they do different jobs?
Step 1 / 10