Mitosis makes identical daughter cells

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Learning goals Lecture 7, Mitosis and Meiosis
Text Reading Chapter 12, Overview, pp. 218 - 226
(stop at Binary Fission) also, Fig. 12.8
(chromosome movement) is not required. Chapter
13 (all).
You need to be able to explain the following to
yourself and to me (on exams)
Mitosis makes identical daughter cells Where it
occurs (functions) produces identical daughter
cells, cell cycle, stages (interphase, prophase,
prometaphase, metaphase, anaphase, telophase,
cytokinesis), sister chromatid
Meiosis makes haploid gametes sexual
reproduction, haploid, diploid, gamete,
homologous chromosome, the two stages of meiosis,
reductional division, independent assortment,
chiasma  
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Figure 12.2 The functions of cell division
Mitosis functions sister chromatids cell
cycle Stages cytokinesis
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Figure 12.4 Chromosome duplication and
distribution during cell division
Mitosis functions sister chromatids cell
cycle Stages cytokinesis
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Figure 12.5 The cell cycle
Mitosis functions sister chromatids cell
cycle Stages cytokinesis
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Figure 12.6 Exploring The Mitotic Division of an
Animal Cell
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Figure 12.6 Exploring The Mitotic Division of an
Animal Cell
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Terms to know about stages of mitosis

• Centromere - a constriction especially easily
  seen at metaphase, containing the area to which
  the spindle fibers attach.
• Kinetochore - the specific small part of the
  centromere to which the spindle fibers attach.
• Spindle fibers - microtubules of protein that can
  move chromosomes.
• Centrosome - the region that forms at opposite
  ends of the cell during mitosis, where the
  spindle fibers converge.
• Centriole - a small structure in the middle of
  the centrosome.
• Aster - a description of the centrosome growing
  spindle fibers - this looked to early cell
  biologists like a star, hence aster.
• Microtubule - fibers, made of proteins, that move
  chromosomes (among other things)

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Terms about mitosis not covered in lecture (thus
very unlikely to be on exam)

• Kinetochore vs Nonkinetochore microtubules -
  dont need to know distinction.
• Nucleolus - organelle concerned with making
  ribosomes.
• Centriole - small paired organelles of somewhat
  mysterious function, that are located in animal
  asters - but are not necessary for mitosis.

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Figure 19.2 Levels of chromatin packing - just
know that it happens!
Mitosis functions sister chromatids cell
cycle stages cytokinesis
Metaphase in light microscope
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Figure 12.9 Cytokinesis in animal and plant cells
Mitosis functions sister chromatids cell
cycle stages cytokinesis
Vesicle small membrane-lined bag
Daughter cells
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Mitoses in onion apical meristem (root tip)
?
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Mitoses in onion apical meristem (root tip)
?
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Figure 13.2 The asexual reproduction of a hydra
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
A fundamental problem - a paradox - for
genetics Heredity - like reproduces like,
but Variation - offspring are never exactly like
their parents Sexual reproduction and meiosis are
important parts of the resolution of this
paradox. Sexual reproduction means that special
reproductive cells, or gametes, are produced.
These fuse at fertilization (syngamy) to make a
zygote.
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Figure 13.5 The human life cycleHaploid means
that the cell has a single complete genome, and
one of each chromosome (n). Diploid means that a
cell has two complete genomes, and two of each
chromosome (2n).exceptions later
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Figure 13.6 Three types of sexual life cycles
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Figure 13.4 Describing chromosomes in a diploid
cell at metaphase - in a eukaryote
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
Why do we bother with coloring the chromosomes
from mom and dad differently? Because they could
have slightly different versions of genes - they
could vary. Ultimately, variation is due to
mutation, but we are getting ahead of ourselves.
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Figure 13.7 Overview of meiosis how meiosis
reduces chromosome number
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Figure 13.8 The Meiotic Division of an Animal Cell
Meiosis two stages of meiosis
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Figure 13.8 The Meiotic Division of an Animal Cell
Meiosis two stages of meiosis
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Figure 13.9 A comparison of mitosis and meiosis
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Figure 13.10 The independent assortment of
homologous chromosomes in meiosis
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Figure 13.11 The results of crossing over during
meiosis
Meiosis sexual reproduction haploid, diploid,
gamete homologous chromosome two stages of
meiosis independent assortment crossing-over
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Learning goals Lecture 7, Mitosis and Meiosis
Text Reading Chapter 12, Overview, pp. 218 - 226
(stop at Binary Fission) also, Fig. 12.8
(chromosome movement) is not required. Chapter
13 (all).
You need to be able to explain the following to
yourself and to me (on exams)
Mitosis makes identical daughter cells Where it
occurs (functions) produces identical daughter
cells, cell cycle, stages (interphase, prophase,
prometaphase, metaphase, anaphase, telophase,
cytokinesis), sister chromatid
Meiosis makes haploid gametes sexual
reproduction, haploid, diploid, gamete,
homologous chromosome, the two stages of meiosis,
reductional division, independent assortment,
chiasma