In mammalian cells, the first sign of mitosis beginning is the
(A) Appearance of chromosomes
(B) Separation of chromatids
(C) Disappearance of the cell membrane
(D) Replication of chromosomes

The cell cycle is a series of events in the life of a dividing eukaryotic cell. It consists of four stages: G₁, S, G₂, and M. The duration of the cell cycle varies from one species to another and from one cell type to another. The G₁ phase varies the most. For example, embryonic cells can pass through the G₁ phase so quickly that it hardly exists, whereas neurons are arrested in the cell cycle and do not divide.

Transcribed Image Text:

M mitosis) G₁₂ 4 hours 9 hours S- -G₁ 10 hours