Download The Cell Cycle

SC- B-2.6: Summarize the characteristics of the cell cycle:
interphase;the phases of mitosis, and plant & animal
cytokinesis
in nuclei of eukaryotic cells
 made up of:
1. DNA
2. Histones: proteins DNA wraps
around
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series of events that cells go through
as they grow & divide
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What a cell does in the cell cycle:
 grow
 prepares for division
 divides into 2 daughter cells
time between cell divisions
 3 divisions:
1. Gap 1 (G1)
2. S Phase
3. Gap 2 (G2)
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cells do most of their growing
make proteins & organelles
checkpoint
cells destined never to divide again
leave cell cycle & enter G0
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synthesis phase
chromosomes duplicated
cells that enter S destined to go thru
mitosis
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usually shortest part of interphase
material needed for cell division
produced
checkpoint
4 phases:
1. Prophase
2. Metaphase
3. Anaphase
4. Telophase
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each phase may last minutes to days
depending on cell type
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longest phase of mitosis
chromosomes become visible
(chromatin condenses)
centrioles separate & move to
opposite sides of nucleus
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centrioles start to organize mitotic
spindle
nuclear envelope & nucleolus
disappears
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chromosomes line up across center
of cell = metaphase plate
centromere of each chromosome
connected to spindle fiber
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centromeres split pulling sister
chromatids apart
as soon as split they are called
chromosomes
as long as they are moving they are
in anaphase
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chromosomes disperse & are no
longer visible
2 nuclear envelopes reform & each
nuclei starts to form a nucleolus
spindle breaks apart
cleavage furrow becomes visible
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cytoplasm pinches in half  each
daughter cell has identical set of
duplicate chromosomes
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rigid cell wall cannot “pinch” in half
Cell plate starts to form during
telophase cell wall between 2
daughter cells