Pre-IB Biology Cellular Reproduction part 2: Meiosis CH8 (p130-139)
3 key components to Reading
Notes___________________________________________________________
1) Preview: (3- 4 sentences/bullets) – “I think I am going to learn…”
(before starting a close reading of the text, preview the assigned reading by – reading headings and subheadings, the topic sentences of each paragraph, the bold words, looking at the figures and reading their captions)
2) Reading Notes
Left side
Right side
Main ideas/ Pictures
Detailed information: Highlight key terms/ key concepts (10-30% of notes)
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3) Summary:
At the End of the Reading notes: Draw a line to separate the notes from the Reading SUMMARY (see options below)
1) Summary paragraph write a 5-8 sentence paragraph about what you learned. OR
2) Graphic summary: Create, draw, label a visual summary of the information and write a 10-20 word caption of how the graphic summarizes what key concepts were learned from the reading.
RN5: Meiosis, the Basis of Sexual reproduction (p130-131)
Main ideas
Reproduction intro
Homologous
Chromosomes
Draw and label Pair of
homologous chromosomes from top of Fig
8.13
Gametes and the life cycle
of a sexual organism
Making a baby
Conclusion paragraph/ fig
8.15
Information prompts
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“like begets like”
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Sexually reproducing organisms
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Purpose of fig 8.12
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Spears and Pitt
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A somatic cell is…
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____ Number of chromosomes in a human
somatic cell
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Karyotypes show (include info from fig 8.13 too)
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Homologous chromosomes and genes
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Mammal sex chromosomes
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Autosomes
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Life cycle
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Explain fig 8.14
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Diploid v. haploid
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Humans 2n =
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Humans n=
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Use correct scientific terms to describe
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Purpose of alternating diploid and haploid stages
of life cycle
RN7: The origins of Genetic variation (135-136)
Main ideas
Intro paragraph
Independent Assortment
of Chromosomes
RN6: The process of Meiosis (p132-133)
Main ideas
Meiosis
Exchange of genetic
material
Fig 8.16 The stages of
meiosis
Information prompts

Meiosis produces
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Meiosis I  Meiosis II
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Crossing over
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Function of Red v. Blue coloring
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Interphase (draw/label describe key event)
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Meiosis I
o
Prophase I (draw/label/
describe key event)
o
Metaphase I (draw/label/
describe key event)
o
Anaphase I (draw/label/
describe key event)
o
Telophase I and Cytokinesis
(draw/label/ describe key
event)
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Meiosis II (draw/label/ describe key event)
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Random Fertilization
Summary Prompt
Connect the human life cycle and chromosomal inheritance
to you and your biological parents.
Information prompts

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Crossing over
Draw/label fig 8.19
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Purpose
How does fig 8.18 show meiosis contributes to
genetic variation?
Make this personal! If the red represents the
chromosomes you inherited from you mom and the
blue represents the chromosomes you inherited from
your father, then when your ovaries or testies produce
gametes which of your gamete combinations would
contain…
o
Only your Father’s
chromosomes?
o
Only your Mother’s
chromosomes?
o
Both your father and mothers
chromosomes?
How are combination c and d different?
“flip of a coin”
Chromosome combination calculation
o
Equation
o
n is…
o
human calculation w/ explanation
Explain how random fertilization can add a huge
amount of variability to the offspring produced by
sexual reproduction?
Excepting identical twins, explain why it is
improbable that two siblings would be genetically
identical.
Crossing over:
Explain how crossing over contributes to genetic
variation
Explain fig 8.19
Why not surprised that gametes and the offspring that
results from them can be so varied?
Summary Prompt
Pretend you just found out your biological mother is expecting a baby
with your biological father* – why will this baby be genetically similar to
you, but NOT genetically identical. * Yes I know this is not practically possible/ or
desirable for some of you 
RN8: When Meiosis Goes Awry (137-139)
Main ideas
Intro paragraph
How Accidents during
Meiosis can alter
chromosome number
Summary Prompt
Information prompts
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Compare and contrast Mitosis (p126-127) with Meiosis
Down syndrome: an extra
Chromosome 21
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Abnormal numbers of Sex
chromosomes
Klinefelters syndrome
Uncomplicated
Turners Syndrome
Sex determination
Summary Prompt
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Purpose
Nondisjunction
Fig 8.20 a Nondisjunction during anaphase I
Fig 8.20 b Nondisjunction during anaphase II
Describe possible fertilization consequences (2nd
paragraph/ fig 8.21)
What might explain an increase in nondisjunction in
eggs produced by older women?
How is fig 8.22 different from a normal human
karyotype?
Why aren’t more babies born w/ an abnormal
chromosome number?
Down syndrome symptoms/ complications (list atleast
5)
Statistics on Maternal age and Down syndrome
Why might mammals better be able to tolerate an
abnormal number of sex chromosomes?
o
Y
o
X
Chromosomal abnormality
Sex
Symptoms/ complications
What two sex chromosomes don’t lead to
complications?
Chromosomal abnormality?
Sex
Complications
Y!
Pretend it is 10-30 years from now, and you are expecting your first
child…would you want to find out if you’re having a boy or a girl? Would
you want to test for chromosomal abnormalities? Why or Why Not?