CELL DIVISION

Mitosis

WHAT IS MITOSIS?

Part of eukaryotic cell division during

which the cell nucleus divides.

Results in the formation of 2 identical

daughter cells.

Mitosis is completed in 4 distinct

steps.

THE CELL CYCLE

Mitosis takes up

very little of the life

time of a cell.

90% of the time our

cells are in between

cell divisions.

We call this in

between time

INTERPHASE.

INTERPHASE

There are 3 phases of interphase in which the cell is

carrying out different functions.

• G1: First phase of interphase in which a cell does most of its growing. They increase in size and synthesize new proteins and organelles.

• S: The second phase of interphase. Chromosomes are replicated and the synthesis of DNA molecules takes place.

• G2: Third phase of interphase. The cell prepares itself for mitosis.

PHASES OF MITOSIS

Biologists divide the events of mitosis into

four phases: Prophase, metaphase, anaphase,

and telophase.

IPMAT. IPMAT?

An easy device to help remember the steps of

the cell cycle in the correct order. Interphase,

Prophase, Metaphase, Anaphase, Telophase.

PROPHASE

First and longest stage

of mitosis, during which

the chromosomes

become visible and the

centrioles separate and

take up positions of the

opposite sides of the

nucleus.

PROPHASE (CONT.)

The nuclear membrane

and nucleolus disappear

during prophase. The

spindle fibers begin to

form and attach

themselves to the

centromeres of the

chromosomes

METAPHASE

Second phase of mitosis,

during which the

chromosomes line up across

the center of the cell.

ANAPHASE

Third phase of

mitosis, during

which the

chromosome

pairs separate

and move

toward opposite

poles.

TELOPHASE

Fourth and final

phase of mitosis,

during which the

chromosomes begin

to unravel back into

chromatin.

The nuclear

membrane and

nucleolus reform.

CYTOKINESIS

Cytokinesis, while technically

not a part of mitosis, results in

the physical splitting of the

cytoplasm.

The sides of the cell membrance

pinch inwards creating a

cleavage furrow.

Afterwards, the two new

daughter cells will enter the G1

phase of interphase.

PUTTING IT TOGETHER

Mitosis in action