Transcript Ch 9 The Cellular Basis of Life

Ch 9 The Cellular Basis of Life
9.1 Cells come from Cells
Cells are needed for
Mitosis: repair, growth,
asexual reproduction (clones of one parent)
Meiosis: sexual reproduction
(two parents)
Video clip (3 minute overview of mitosis/cancer)
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9.2 The cell cycle multiplies cells
Different number of chromosomes for each
organism (humans have 46)
Interphase:
Chromosomes
duplicate
before the
cell divides
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Mitosis- nucleus divided
 and Cytokinesis-cell divides
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9.3 Mitosis
Prophase=pairs
Metaphase=middle
Anaphase=away
Telophase=two
Cytokinesis animals
Cell plate plants
Onion root tip
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9.4 Cancer
 Cancer is due to uncontrolled cell cycle
 Benign –local tumor
 Malignant- travels around body by
metastasis
 Treatment=surgery, radiation,
chemotherapy
(some disrupt mitotic spindle)
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9.5 Meiosis is used in sexual reproduction
 Meiosis only occurs in sperm and egg so
the new offspring doesn’t have double the
chromosome number
 Diploid
 Haploid
 Chick embryo
 Pig embryo
 Human embryo
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Meiosis- two divisions
Results in four
 cells

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9.6 Meiosis increases genetic
variation
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Crossing over

In Meiosis
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