Download Cell Cycle

Cell Cycle
THe Cell Cycle
Pmat + Cytokinesis
· mitosis - division of the nucleus
PMAT (prophase, metaphase, anaphase, telophase)
start: 46 chromosomes
end: 46 chromosomes
· cytokinesis - division of the cytoplasm
· meiosis - formation of gametes (egg and sperm)
start: 46 chromosomes
end: 23 chromosomes
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Interphase
· 3 stages
G1 - growth and duplication of organelles
S - DNA replication
G2 - growth and duplication of organelles
· period of preparedness
Prophase
· chromosomes visible as 2 sister chromatids
identical copies held together by a centromere
· centrioles move to opposite ends of the cell
· nuclear envelope and nucleolus disappear
· microtubules form
aka spindle fibers
Metaphase
· chromosomes line up along the cell's midline
· spindle fibers attach to centromeres
Anaphase
· shortest phase
· chromatids separate as spindle fibers shorten
and pull individual chromosomes to opposite
ends of the cell
· easy to recognize b/c chromosomes look V
shaped
Cell Cycle
Telophase
·
·
·
·
prophase in reverse
chromosomes unwind
nuclear envelope and nucleolus reappear
microtubules disappear
Cytokinesis
· begins during anaphase
· cleavage furrow pinches the cell apart
· end result
2 identical daughter cells each with their own
nucleus and organelles