Section 10.2 (Pg. 279-285):
The Process of Cell Division
Eukaryote
Chromosomes
- Are genetic information bundled
into packages of DNA
- Make it possible to separate DNA
precisely during cell division
- Are packaged differently in
prokaryotes and eukaryotes
- Prokaryotes: small, circular
chromosome
- Eukaryotes: multiple chromosomes
Prokaryote
Eukaryotic Chromosomes
- Are made of chromatin
- DNA coils around proteins called histones
- DNA coiled around histones forms a unit
called a nucleosome
- Chromosome shape is supercoiled
chromatin
Prokaryotic Cell Cycle
- Prokaryotic cell division is called
binary fission
1) Cell grows and chromosome duplicates
2) Cell membrane pinches in
3) Cell divides into two daughter cells
Prokaryotic Cell
The Eukaryotic Cell Cycle
- Is when a cell grows, prepares for
cell division, then divides
- Is separated into two major parts:
1) Interphase
2) Cell division
- Interphase and cell division have
their own phases
Interphase
- Is the portion of a cell’s life in between
cell division
- G1 phase: Cell Growth
– Cell grows and performs normal functions
- S phase: DNA Synthesis
– DNA is copied for cell division
- G2 phase: Preparation for Cell Division
– Organelles and molecules are copied for cell
division
Cell Division
- Is also called M phase
- Contains the phases of cell division
- Mitosis
– Is the division of the nucleus
– Has 4 separate phases
- Cytokinesis
– Is the division of the cytoplasm
DNA During Cell Division
- Forms replicated chromosomes
– Each half of the chromosome is
called a sister chromatid
– They are held together by a
centromere
- Is separated into daughter
chromatids during cell division
Before Cell Division
- Cells are in interphase
– Nucleus is intact
– DNA has NOT yet formed
chromosomes
– Centrioles are lumped together near
the nucleus