Transcript Ch 10 Cell Growth and Division

1 Review What are chromosomes
Compare and Contrast How does the structure of
chromosomes differ in prokaryotes and eukaryotes
2 Review What happens during each of the four
phases of mitosis- write one or two sentences about
each
Predict What do you think would happen if the
spindle fibers were disrupted during metaphase
CH 10 CELL GROWTH AND DIVISION
10.2 The Process of Cell Division
Chromosomes




Carries and passes on genetic information from one
generation to another
Each cell must copy its genetic information before
cell division begins
Each daughter cell gets its own copy
Different organisms have different number of
chromosomes.
Prokaryotic Chromosomes


Most prokaryotes contain a single, circular
chromosome
Located in the cytoplasm (no nucleus).
Eukaryotic Chromosomes


Located in the nucleus
Made up of chromatin
 DNA
and histone proteins.
Eukaryotic Chromosomes

Chromatin is DNA and histone proteins.
Eukaryotic Chromosomes

DNA coils around histones to make nuclesome.
Eukaryotic Chromosomes

Nucleosomes coil and form supercoils that form
chromosomes.
The Prokaryotic Cell Cycle


Regular pattern of growth,
DNA replication, and cell
division
Binary fission
 Asexual
reproduction
 Two genetically identical cells
are produced.
The Eukaryotic Cell Cycle


G1, S, G2, and M
Interphase is G1, S, and
G2.
G1 Phase: Cell Growth

Cells increase in size and
synthesize new proteins
and organelles.
S Phase: DNA Replication

New DNA is synthesized
(chromosomes are
replicated).
G2 Phase: Preparing for Cell Division

Organelles and
molecules are produced.
M Phase: Cell Division

Mitosis


Division of the cell nucleus
Cytokinesis

Division of the cytoplasm.
Cell Structures Involved in Mitosis

Chromatid
 Each

Centromere
 Area

strand of a duplicated chromosome
where each pair of chromatids is joined
Centrioles
 Tiny
structures in cytoplasm of animal cells that help
organize the spindle

Spindle
 Fanlike
microtubule structure that helps separate the
chromatids.
Mitosis



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Prophase
Metaphase
Anaphase
Telophase.
Prophase

Chromosome condense
and become visible.
Prophase


Chromosome condense
and become visible
Centrioles move to
opposite sides.
Prophase



Chromosome condense
and become visible
Centrioles move to
opposite sides
The spindle forms.
Prophase




Chromosome condense
and become visible
Centrioles move to
opposite sides
The spindle forms
Nucleolus disappears
and nuclear envelope
breaks down.
Metaphase

Chromosomes line up
across the center of the
cell.
Metaphase


Chromosomes line up
across the center of the
cell
Spindle fibers connect
the centromere.
Anaphase

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The chromatids separate
Chromosomes are pulled
to opposite ends.
Telophase



Chromosomes arrive at
poles
Nuclear envelope
reforms
Spindle breaks apart.
Animal Cytokinesis

Cell membrane is drawn in until the cytoplasm is
pinched into two equal parts containing its own
nucleus and organelles.
Plant Cytokinesis

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
Cell plate forms between the divided nuclei
Forms into a cell membranes
Cell wall created between the membranes.