Download The Cell Cycle

Who likes to dance?
Our chromosomes like to
dance during Mitosis.
Mitosis Animation
What is Cell Division?
The process by which a cell divides into
2 new daughter cells.
What happens to the chromosomes
before a cell divides?
The chromosomes need to be
replicated before a cell divides.
Chromosomes
What are chromosomes made
up of?
DNA and Protein
The chromosomes are replicated
before a cell divides.
Centromere
Chromatids
Chromosome
Replication
Chromosome
2 Chromatids
+ Centromere
When do cells divide?
Organism Growth
Cells at the root tips divide very rapidly
When do cells divide?
Repair
When do cells divide?
Regeneration
The ability of organisms to grow
back limbs if they are cut off.
What tissues in our body need
to undergo a lot of cell division?
Skin
Stomach
Why?
Bone
The cells of these tissues are
constantly growing or repairing
themselves.
Cell Cycle
1) G1 Phase- Cells increase in size and
synthesize new proteins and organelles.
2) S Phase- DNA (chromosomes) are
replicated.
3) G2 Phase- Many of the molecules and
organelles for cell division are produced.
4) M Phase- the cell undergoes cell division.
Does anybody know what the “M” stands for?
Mitosis
What are the phases of the Cell
Cycle?
G1- Cells increase in size and
synthesize new proteins and
organelles.
Cell
Cell
What are the phases of the Cell
Cycle?
S Phase- DNA (chromosomes)
are replicated.
Centromere
Chromatid
What are the phases of the Cell
Cycle?
G2 Phase- Many of the molecules
and organelles for cell division are
produced.
G1, S, and G2 Phases are
collectively known as:
Interphase
Chromatin
Centriole
What are the phases of the Cell
Cycle?
M Phase- the cells undergo cell
division.
What does the “M” stands for?
Mitosis
The dance of the
Chromosomes
Stages of Mitosis:
Prophase:
1) The chromosomes become
visible.
2) The centrioles separate and
Spindle fibers begin to form.
Centriole
Nuclear
Membrane
3) The nuclear membrane breaks
down.
Spindle Fibers
Stages of Mitosis:
Metaphase:
1) The chromosomes line up
across the center of the cell.
2) Each chromosome is connected to
a spindle fiber at the centromere.
Stages of Mitosis:
Anaphase:
1) The spindle fibers separate
the chromatids into individual
chromosomes and are they
are moved apart.
Stages of Mitosis:
Telophase:
1) The chromosomes gather at opposite
ends of the cell.
2) Two new nuclear membranes form.
3) The chromosomes lose their distinct
shapes.
Cytokinesis:
The cytoplasm pinches and two cells
are formed.
What is the end result of Mitosis?
46X
Parent
+
46X
Daughter Cell
Chromosome Number?
The same number of
chromosomes is maintained
from one generation to the
next.
46X
Daughter Cell
Is the genetic material of the
daughter cells identical to the
parent?
YES
Mitosis Phases
Prophase Metaphase
Cytokinesis
Anaphase
Telophase
Which phase are these cells in?
Prophase
Anaphase
What phase are these cells in?
Telophase
Metaphase
How does plant and animal cell
mitosis differ?
• Plant cells do NOT have centrioles
• During telophase, plant cells form a cell
plate which eventually becomes the cell
wall
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