Chapter 9
Cellular Reproduction
9.1 Cells grow until they reach their size limit, then they either stop growing or divide.
Vocabulary Words
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Cell Cycle – the process of cellular reproduction, occurring in three main stages –
interphase (growth), mitosis (nuclear division), and cytokinesis (cytoplasm division).
Interphase – the first stage of the cell cycle, during which a cell grows, matures, and
replicates its DNA
Mitosis – the second main stage of the cell cycle during which the cell’s replicated DNA
divides and two genetically identical diploid daughter cells are reproduced.
Cytokinesis –
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Chromosomes –
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Chromatin -
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Notes:
Cell Size Limitations
 Ratio of surface area to volume
 Transport of Substances
 Cellular Communications
The Cell Cycle
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o The stages of interphase
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o Mitosis and cytokinesis
o Prokaryotic cell division
9.2 Eukaryotic cells reproduce by mitosis, the process of nuclear division, and cytokinesis, the
process of cytoplasm division.
Vocabulary Words
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Prophase
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Sister Chromatids
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Centromere
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Spindle Apparatus
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Metaphase
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Anaphase
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Telophase
Notes
Mitosis
o This is when the cell’s replicated genetic material separates and the cell prepares to split
into two cells
o The key activity of mitosis is the accurate separation of the cell’s replicated DNA
o Scab – under the scab, existing skin cells divided by mitosis and cytokinesis to create new
skin cells to fill in the cut
The Stages of Mitosis
 Prophase – the first stage of mitosis. This is where the cell spends most of its time. The
cell’s chromatin condenses (tightens) into chromosomes
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http://biologyblock.com/?p=111
 Metaphase – the second stage of mitosis. The sister chromatids are pulled by motor
proteins along the spindle apparatus toward the center of the cell and line up in the middle
of the cell.
o This is one of the shortest stages but ensures the new cells have accurate copies of
the chromosomes.
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http://biologyblock.com/?p=111
 Anaphase – the third stage of mitosis
o During this stage, the chromatids are pulled apart.
o The microtubules of the spindle apparatus begin to shorten. This causes the sister
chromatids to separate into two identical chromosomes.
o All the sister chromatids separate at the same time, but what controls this is still
unknown.
o At the end of this stage, the microtubules, with help from the motor proteins, move
the chromosomes toward the poles of the cell.
o
http://biologyblock.com/?p=111
 Telophase – the last stage of mitosis. The chromosomes arrive at the poles of the cell and
begin to relax or de-condense.
o Two new nuclear membranes begin to form and the nucleoli reappear.
o The spindle apparatus disassembles and some of the microtubules are recycled by
the cell to build various parts of the cytoskeleton.
o
http://www.digitalwebb.com/Downloads/LabBench/learning/mitosis/telophas.html
Cytokinesis
Begins at the end of mitosis.
This is where the cytoplasm divides
This results in two cells with identical nuclei
Animal Cells –
Plant Cells –
Cell Walls Prokaryotic cells -
http://www.warrenhills.org/Page/3500
9.3 The normal cell cycle is regulated by cyclin proteins.
Vocabulary Words
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Cyclins
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Cyclin-dependent kinases
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Cancer
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Carcinogens
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Apoptosis
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Stem Cells
Notes
Normal Cell Cycle
 The role of cyclins
 Quality control checkpoints
Abnormal Cell Cycle: Cancer
 Causes of cancer
 Cancer genetics
Apoptosis
Stem Cells
 These are unspecialized cells that can develop into specialized cells under the right
conditions.
o Embryonic stem cells
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o Adult stem cells
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