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MITOSIS
MITOSIS
What is the cell cycle?
GrowthAnd
Division
What is Mitosis?
Nuclear Division
What is Chromatin?(Thin Chromatin)
Stretched out, unwound DNALooks like spaghetti
Not visible under microscope
What is a Chromosome?
Coiled up (condensed) version of chromatin; easier for moving DNA
(Looks like a slinky)
What is the Centromere?
Holds Sister Chromatids togetherWhere spindle fibers grab chromosome(Think: Centro = center mere = middle)
What is the Sister Chromatid?
Two identical strands of a chromosome
What are the Centrioles?Organelle that is present only in
ANIMAL CELLS and creates the spindle
fibers“Centrioles go to
the poles”
Name the phases of the Cell Cycle…
G1 PhaseS PhaseG2 PhaseM Phase
What happens in the G1 Phase?
Growth Phase When cell gets bigger and makes lots of proteins1st part of Interphase
What happens in the S Phase?
“Synthesis” PhaseMakes a copy of the DNASingle strand →Double strand2nd part of Interphase
What happens in the G2 Phase?
“Growth 2” PhaseCell is getting ready to divideGetting organelles and proteins(Like going to grocery store to get the food to prepare dinner)3rd part of Interphase
What happens in the M Phase?
“Cell Division” Mitosis and Cytokinesis
Interphase
What is the“Cell Growth and Protein Synthesis” stage that is the
longest phase of the Cell Cycle?(NOT part of Mitosis)
Includes: G1, S, G2
Name the phases of Mitosis (Nuclear division)
ProphaseMetaphase PMATAnaphaseTelophase
“The Professional Met Ana on the Telophone.”
When is the chromatin coiling (visible) under the microscope?(phase)
Prophase
Name each phase of Mitosis (not in correct order)
Metaphase
Telophase
Anaphase
Prophase
What happens in Prophase? “Prepare” Longest phase of Mitosis!!!•Chromosomes coil up to make easy to move•Nuclear envelope (membrane) dissolves•Centrioles make spindle fibersSpindle fibers (muscles of chromosome) form to help move
“Middle”Chromosomes are lined up in the
middle of the cellSpindle fibers are attached and
centrioles go to the poles
What happens in Metaphase?
What happens in Anaphase? “Apart”
Chromosomes get pulled apart by spindle fibers
What happens in Telophase? “The End” or “Tidy Up”
Uncoiling of chromosomesNuclear envelope reforms
Spindle fibers go “bye-bye”
CytokenesisThis is part of Telophase.
Hint: cytoplasmgets Kut
What is Cell Cytoplasm & Membrane Division called?Actual cell division into two cells dividing into two daughter cells
Cytokenesis in Animal CellsWhat structure appears?
Creates a CLEAVAGE FURROW
(Think: Animals have fur)
Cytokenesis in Plant CellsWhat structure appears?
Creates a CELL PLATE
(Think: Hard cell wall is like a hard plate)
What are the two new identical cells made in cell division called?
1 cell divides into2 new cells
2 Daughter Cells
What is it called when a mass of cells are growing out of control?
TUMOR
What signals a cell to start the cell cycle?
Cyclins
Why do normal cells stop growing when they touch other cells or reach the sides of a petri dish?Contact with other cells or the sides of the dish signal to the cell to stop growing.
This happens when you cut your finger. The cells grow rapidly to fill in the cut. When the cells touch, they go back to normal cell cycle.
What are internal regulators and external regulators?Internal regulators are proteins that respond to events inside the cell to tell it when to go to the next phase of cell cycle.
External regulators are proteins that respond to events outside the cell and tell the cell to speed up division then slow down to normal again.
What is it called when cells have lost their ability to control their growth?
Cancer
