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 Cytokinesis Division of the cell nucleus Cytokinesis Division of the cytoplasm.

Cell Structures Involved in Mitosis Chromatid Each strand of a duplicated chromosome Centromere Area 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 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 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 Cell plate forms between the divided nuclei Forms into a cell membranes Cell wall created between the membranes.