Biology 11.3 The Cell Cycle

The cell cycle

Cells don't divide continuously, they undergo regular cycle of division separated by periods of cell growth = cell cycle.

Three stages:

1) Interphase = occupies most of the cell cycle, known as resting phase (no division takes place), divided into 3 parts:

• First growth (G1) phase - proteins produced that synthesise organelles.
• Synthesis (S) phase - DNA is replicated.
• Second growth (G2) phase - organelles grow and divide, energy stores are released.

2) Nuclear division = nucleas divides into two or four (mitosis or meiosis).

3) Cell division = process by which whole cell…