Cell Division
Chapter 2 lesson 3
Objective: Understanding the
functions of cell division
Why do cells divide?
Growth of an organism
Repairing damaged structures ex. If you skin
your knee
Reproduction- especially for single celled
organisms such as
amoebas
The Cell Cycle
Occurs in three stages
Involves cell growth, preparing for division,
and then division into two new cells
The two new cells are called daughter cells
Each daughter cell then begins the cell
cycle again
Three main stages: Interphase, Mitosis,
Cytokinesis
Stage one: Interphase
The cell grows to full size and produces the
organelles it needs
The cell then makes an exact copy of DNA in
the nucleus. This is called replication
DNA gets packaged into chromosomes
Each cell created will contain an identical
sets of chromosomes
Cells produce structures that will help with
cell division
Stage 2: Mitosis
 The cell nuclei divides into two new nuclei and one set
of DNA goes to the daughter cells
 Four stages
 Prophase- nuclear envelope breaks down, spindle
fibers form and connect at opposite sides,
chromosomes condense.
 Metaphase-chromosomes, attached to spindle fibers,
line up in the center of the cell
 Anaphase- chromatids split and move to opposite
sides of the cell
 Telophase- spindle fibers disappear, nuclei are
forming, cell is pinched in the middle
Stage three: Cytokinesis
Completes process of cell division
Each Daughter cell has the same number of
chromosomes and is an exact copy of the parent cell
 Animal Cells- the cell membrane squeezes together
around the middle of the cell
 Plant Cells- cell plates form across the middle of the
cell, new cell walls develop