Mitosis: Cells at Work!!. What is Mitosis? Part of the cell cycle Nuclear cell division during which...
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Transcript of Mitosis: Cells at Work!!. What is Mitosis? Part of the cell cycle Nuclear cell division during which...
Mitosis: Cells at Work!!
What is Mitosis? Part of the cell cycle Nuclear cell division during which
chromosomes are equally distributed to the 2 identical daughter cells that are formed
Results in growth Continuous process 4 stages
What is the cell cycle? Continuous sequence of growth and
division of a cell. 2 parts: Interphase & Mitosis
Busiest and longest section is INTERPHASE
Phases of Interphase G1 phase – Growth and Protein Synthesis S phase – DNA Replication G2 phase – Checkpoint to make sure cell
is ready to undergo mitosis
Mitosis Stage 1: Prophase
•Chromatin coils up into chromosomes
•Nucleus begins to disappear
•Centrioles migrate to opposite ends of cells and spindle forms
What is a chromosome?
• The condensed form of the original DNA connected to its identical copy • Sister Chromatids
MitosisStage 2: Metaphase
•Chromosomes attach to spindle fibers
•Chromosomes line up along the equator of the spindle
•Very short phase
MitosisStage 3: Anaphase
•Begins as sister chromatids separate
•Centromeres split apart
•Chromatids are pulled to opposite poles of the cell
MitosisStage 4: Telophase
•Begins as chromatids reach the poles
•Chromosomes unwind and spindle breaks down
•New nuclei form around each set of chromosomes
•Plasma membrane separates
Cytokinesis: Division of the cytoplasm Animal cell Plasma membrane
pinches along equator
Forms a cleavage furrow that deepens until the cell is pinched in two
Plant cell Plasma membrane
does not pinch in b/c of rigid cell wall
Cell plate forms at the equator that divides the cytoplasm
Cytokinesis: Division of the cytoplasm
I Pour Milk And Tea
I—Interphase “The Xerox phase” P—Prophase “Cell PREPARES and
chromosomes become visible” M—Metaphase “The chromosomes
line up in the MIDDLE” A—Anaphase “The chromosomes pull
APART” T—Telophase “The TWO identical
daughter cells separate”
Purpose of Mitosis (Cell Division) AFTER mitosis, the 2 new daughter cells
will be identical. Each new cell receives the correct
number of chromosomes for that organism (Humans = 46 chromosomes)
23 from mom, 23 from dad When both sets of chromosomes are in
a cell, it is said to be diploid. All somatic (body) cells are diploid.
Applications of Cell Division Regeneration of tissue after
transplantation Regeneration of body parts (ex.
Starfish) Spinal cord injuries Specialized cells for
transplantation Embryo Development Ensures that the new cells will
make the same proteins as the old cell!!!