1. Intro to Cell Cycle

WHAT YOU HAVE LEARNT BEFORE …  O-level Pure Biology:

WHAT YOU WILL LEARN …  A-level Content:

WHY SHOULD YOU LEARN THIS?

Intro to the CELL CYCLE Pg 1 Lecture Book 4 Pg 1

CELL CYCLE VS CELL DIVISION  Cell cycle:  is the orderly program of events in the lifetime of a cell  From the time it is first formed from a dividing parent until its own division into 2 daughter cells  Cell division:  A process involving the division of a parent cell into new daughter cells.  comprising of nuclear division and cytokinesis Pg 1

TERMINOLOGY Cell Cycle = Interphase + Cell Division Recall: Cell = Nucleus + Cytoplasm Cell Division = Nuclear division + Cytoplasmic Division a.k.a Cytokinesis Mitosis / Meiosis Pg 1

2 TYPES OF NUCLEAR DIVISION 1. Mitosis: produces 2 daughter nuclei that are genetically identical to that of the parent. The daughter cells should have the same number of chromosomes and same genetic information as the parent cell. Pg 1 MITOSIS PARENT DAUGHTERSMore in MITOSIS lecture!

2 TYPES OF NUCLEAR DIVISION 2. Meiosis: Involves 2 nuclear divisions. This produces 4 daughter nuclei that are not genetically identical have half the number of chromosomes as that of the parent. Pg 1 MEIOSIS Meiosis I Meiosis II Details not needed in H1!

MITOTIC CELL CYCLE OVERVIEW Mitotic cell cycle is divided into: 1. Interphase (G1, S & G2 phase) 2. Cell division phase comprises of: a. Mitosis* (nuclear division) b. Cytokinesis (division of cytoplasm) Mitotic phase aka “cell division” Pg 1

1) INTERPHASE  A period of synthesis of materials required for carrying out all its functions and growth  Subdivided into G1, S and G2 phases Mitotic phase aka “cell division” Pg 1