Mon Prof Augmenté
One Cell Becomes Two
Age 15 Biology
Before a cell divides, it copies every chromosome so there are two matching sets. The sets are pulled to opposite ends and the cell pinches in half, making two daughter cells with the same genetic instructions.
Step by step
- Copied chromosomes lined up down the middle of the cell
- Spindle fibres pulling one full set toward each end
- The pinched waist where the membrane closes inward
- One of the two finished daughter cells, identical to its partner
Examples
- A scraped knee closing up as skin cells divide to fill the gap
- Fingernails and hair growing longer as cells at the root keep dividing
Key takeaways
- Chromosomes are copied first, so each new cell receives a complete set.
- This kind of division makes two cells genetically identical to the original.
A quiz goes with this lesson
Three questions asked a few days later, to check the idea stuck — not that the picture was seen. In the app, with a subscription.