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Jeremy G. Vicencio

1st Semester, A.Y. 2011-2012

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Technically, not a part of mitosis

Intensive metabolic activity, cell growth,and cell differentiation occur.

Chromosomes are extended anduncoiled, forming chromatin

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Gap 1 Cell prepares for DNA replication.Ribosomes, tRNA, mRNA and severalenzymes are synthesized and the

cytoplasmic mass increases. The centrioleduplicates in late G or early S phase.

S phase DNA replication takes place

Gap 2 The cell prepares for mitosis.Spindle and aster proteins aresynthesized.

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G1 checkpoint check to see if DNA isdamaged

G2 checkpoint check to see if DNA is

replicated properly M checkpoint spindle assembly

checkpoint, check for alignment of

chromosomes If any of the checks fail, the cell undergoes

apoptosis (programmed cell death)

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A form of cell division resulting in theproduction of two cells, each with thesame chromosome and genetic

complement as the parent cell.

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Spindle formation

Centrioles move toopposite poles

Chromosomes becomevisible

Nuclear membrane

starts to disintegrate

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Period of chromosomemovement

Microtubules of

spindle attach tokinetochore onchromosomes

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Chromosomes line upalong the metaphaseplate

The term is appliedstrictly to thechromosome

configuration aftermigration

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The shortest stage ofmitosis

Sister chromatids of each

chromosome disjoin(separate) from eachother and migrate to

opposite poles Splitting of the

centromeric region

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Nuclear membranereforms

Chromosomes unwind

Commencement ofcytokinesis (cellpinches inward and

forms two daughtercells)

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Interphase Prophase Metaphase Anaphase Telophase

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Animal Cell Plant Cell

Centrosome has 2 centrioles Cytokinesis: CLEAVAGE

Cleavage furrow: shallow

groove near metaphase plate Contractile ring of actin

microfilaments at thecytoplasmic side of furrow

Contraction: pulling ofdrawstrings

Deepening of cleavagefurrow

Pinching of cell into 2

Centrosome has 0 centrioles Cytokinesis: CELL PLATE

Vesicles (with cell wall materials)

from the Golgi move along themicrotubules to middle of cell

Coalescence of vesicles

Cell plate formation Cell wall materials collect at cell

plate Cell plate enlarges surrounding

membrane fuse with plasmamembrane 2 daughter cells

Cell wall between daughter cells

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Growth and development of an organism

Repair of damaged tissues/organs

Reproduction (Asexual)

Genetic continuity