Transcript The Cell Cycle - 7th Grade Life Science

THE CELL
CYCLE
The Life Cycle of a cell : includes Growth,
Development, and Reproduction
Importance of Cell
Division
 Growth of Organism
 Repair
 Reproduction for some
organisms
Phases of the Cell Cycle
1. Interphase
 Growth and normal functions (G1)
 DNA replicates – makes a copy of
itself (S)
 Sister chromatids are held together
by the centromere
 Organelle replication
Interphase
2. Mitosis
 Prophase
 DNA condenses forming
chromosomes
 Nuclear membrane breaks down
 Spindle fibers form between
centrioles
Prophase
Mitosis continued
 Metaphase
 Replicated chromosomes line up
across the middle of the cell
 Chromosomes attach to the
spindle fibers at the centromere,
which is still holding the
chromatids together
Metaphase
Mitosis continued
 Anaphase
 Spindle fibers pull the two
chromatids in opposite
directions causing the
centromere to split
 Chromatids move to opposite
sides
 Cell becomes stretched
Annaphase
Mitosis continued
 Telophase
Chromatid unwind forming
chromatin
New nuclear membrane
forms around each set of
chromatin
Telophase
Cell cycle
3. Cytokinesis
 Cell membrane pinches together
forming two cells
 Cell plate form in plant cells ,
eventually forms cell membrane
and wall
Cytokinesis
Results of Cell Division
 Parent cell no longer exists
 Two daughter cells with
identical DNA to the parent
cell form
The cell cycle
INTERPHASE
G1
S
(DNA synthesis)
G2
Animal Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Plant Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
The Cell Cycle