Mitosis During interphase, the DNA is not condensed and individual chromosomes cannot be discerned As the cell enters prophase, the chromosomes condense After DNA replication in S phase, each chromosome has two DNA molecules, known as sister chromatids Until they are separated during anaphase, the chromatids are held together at a region called the centromere

Vocabulary Checkpoint Chromosomes: in Eukaryotes, a structure composed of DNA and proteins that bares part of the genetic information of the cell Chromatid: one of two identical chromosomal strands into which a chromosome splits longitudinally preparatory to cell division. Sister Chromatids: each pair of newly replicated chromatids Centromere: the region where sister chromatids join Spindle: array of microtubules emanating from both poles of a dividing cell during mitosis Centriole: a paired organelle that helps organize the microtubules during cell division

Prophase

Metaphase

Anaphase

Telophase