Biology Reference
In-Depth Information
Figure 3.3
Mitosis of a diploid cell involves duplication of each homologous chromosome and its
distribution to the daughter cells. DNA replication occurs during interphase when the DNA is not
condensed. During prophase, the two daughter chromatids are attached to each other at the cen-
tromere. During metaphase, the highly condensed chromosomes line up on the metaphase plate,
and during anaphase the daughter chromatids separate and begin moving to opposite poles.
During telophase, the nuclear membranes reform, and two identical daughter cells with a complete
complement of chromosomes have been produced.
mitosis and DNA synthesis (S), whereas G
2
is the gap between S and mitosis (M).
The length of a cell cycle varies by cell type, but it typically lasts
≈
18-24 hours,
with mitosis requiring 0.5-2 hours (see Figure 1.14).
Mitosis is divided into four main stages: prophase, metaphase, anaphase, and
telophase (
Figure 3.3
). In
prophase
, the nuclear envelope is still intact, and each
