what are chromatids

Chromatids are the two identical copies of a chromosome made after DNA is replicated. They stay joined at the centromere until cell division, when they separate so each new cell gets a full set of DNA.

Quick Scoop

Think of a replicated chromosome as having two matching halves: each half is a chromatid, and together they are sister chromatids. Before division, the cell copies its DNA; afterward, the chromatids are pulled apart into different cells.

Key points

• A chromatid is one half of a duplicated chromosome.

• The two identical halves are called sister chromatids.

• They are joined at the centromere.

• During cell division, they separate so each daughter cell receives the same genetic information.

Chromatids vs chromosomes

A chromosome is the whole DNA structure, while a chromatid is one of the identical copies after replication. So, after DNA is copied, one chromosome can temporarily look like two chromatids stuck together.

If you want, I can also give you a super-short diagram-style explanation of chromosome vs chromatid vs chromatin.