Transcript Cell division is part of the cell cycle

“Cell division
is part of the
cell cycle”
SECTION 3.2 & 3.3
Do Now!! 
 Label the following diagram:
 1- chromosome
 2- chromatid
 3- centromere
Objectives

To identify the steps of mitosis

To define interphase

To build a cell cycle model using paper plates
The Cell Cycle

The normal sequence of development and division of a cell

Two main phases: Interphase & M-phase (Mitosis)
Interphase
•
There is no division
in interphase, just
growth.
G1: organelles
duplicate, cell grows
S: DNA replicates (is
copied)
G2: cell grows, prepares
to divide
M-phase (Mitosis)

Mitosis: cellular division!

PMAT+ C

Prophase

Metaphase

Anaphase

Telophase

Cytokinesis
Mitosis

Creates 2 genetically IDENTICAL daughter cells.
Prophase

DNA condenses to form chromosomes.


Each chromosome has 2 chromatids and a centromere
The nuclear membrane disappears
Metaphase – “Middle”

Chromosomes line up in the middle of the cell at the
“equator”
Anaphase – “away”

Chromatids split

Spindles pull to opposite sides of the cell AWAY from
each other
Telophase

2 Nuclei form

Nuclear membrane
forms around each
group of
chromosomes.

The chromosomes
become chromatin
again.
Cytokinesis
 Division of the
cytoplasm.
 Occurs differently in
plant and animal cells
 2 new daughter cells!
Do Now!! 

What are the 2 main phases of the cell cycle?

What are the stages of mitosis?

In which stage do the chromosomes line up in the
middle?
Objectives

To compare and contrast cytokinesis in plant and animal
cells

To illustrate and label the stages of mitosis!
Cytokinesis

Animal Cells:

Membrane pinches together and
forms a cleavage furrow until the
cells separate.
Cytokinesis

Plant Cells:

Cell plate forms which
becomes the cell wall and
divides the two cells.
Both sexual and asexual
reproduction involve cell division

Most unicellular organisms use cell division
to reproduce
 Called asexual reproduction- one
organism produces one or more new
identical organisms
 Live independently of parent
 Ex: new skin cells are part of skin tissue
and cannot live independently!
Asexual reproduction: Binary
Fission

A form of asexual reproduction
in prokaryotes

The parent organism splits in
two, creating two new
daughter cells

Genetically all the same!
Asexual Reproduction: Budding

Tiny buds on organisms body

Genetic material the same!

Detaches when it reaches a
certain size

Both unicellular and multicellular
can reproduce by budding

Ex: unicellular- some yeast
multicellular- Hydra
Hydra
Asexual Reproduction:
Regeneration
o
The process of new
tissue growth at sites
with wounds or lost
limbs.
Mexican Axolotl
Newt
Starfish
Bacteria
o
Many bacteria have a very short
generation time
o
Some can have a new generation of
cells in less than 30 min
o
Ex: E. Coli can double every 20 minutes
**Why you get sick so fast!
E. Coli