Download Cell cycle

Cell Division
Biology
HW-VOCAB QUIZ
TOMORROW
1. TAKE OUT NOTES
Cell cycle-process from start to finish
 Cell division/cell cycle-Interphase through Cytokinesis
 Mitosis (M phase) Prophase through Telophase
 Only divides the nucleus NOT the whole cell
Where does the cell cycle/division
occur?
 All somatic (body) cells
 Creates cells that are genetically the same
 Identical DNA
interphase
Interphase-most common and
longest
 G1-cell growth and development
 cell doing the cell’s job
 S-DNA synthesis
 chromatin is copied to make two strands, one for
each new cell
 G2-more cell growth and development
 G0-cell exits the cell cycle and rests
 Nervous cells are in G0
prophase
prophase
 Chromatin thickens to become chromosomes (now visible)
 Centrioles (plant cells do not have these) move to the poles of
the cell
 Chromosomes attach to the newly formed spindle fibers
 Nucleus dissolves
metaphase
Metaphase (m for middle of the cell)
 Chromosomes line up along equator of cell
anaphase
Anaphase (a for apart-chromosomes
move apart)
 Sister chromatids split
 they are pulled centromere first
 Start to reach the opposite poles
telophase
telophase
 Chromosomes elongate and become
chromatin again
 Nucleus reforms
 Spindle fibers break down
Cytokinesis
 Cytokinesis happens-division of the
cytoplasm and organelles using a
cleavage furrow
 Each new cell begins interphase and
starts the cycle all over again.
Plant vs Animal Cytokinesis
 Plants
 Animal Cell
 Form a cell plate in the
 The cell membrane and
middle to divide the cell in
half
 The cell plate will
eventually become the cell
wall.
cytoplasm pinch or cleave
in the middle until 2 cells
are formed
 DO NOT NEED A CELL
PLATE
Microscope Lab
Look at the data table on page 249.
Answer the questions.
• 1. Most wbcs are needed for only a short time to fight
infection so they don’t have to live for a long time.
• 2. Cardiac muscle cells and neurons cannot divide,
injuries to the heart and spinal cord cannot heal. The
cells of smooth muscles can divide and heal through cell
division.
• 3. The cells lining the digestive system are more prone
to be destroyed.
• 4. Cancer cells are long lived and division can occur a
seemingly unlimited number of times.