If you toss a coin, what is the probability of getting heads Tails If you toss a coin 10 times, how

1
Interest Grabber continued

• If you toss a coin, what is the probability of
  getting heads? Tails? If you toss a coin 10
  times, how many heads and how many tails would
  you expect to get? Working with a partner, have
  one person toss a coin
• ten times while the other person tallies the
  results on a sheet of paper. Then, switch tasks
  to produce a separate tally of the second set of
  10 tosses.

Section 11-2
1. Assuming that you expect 5 heads and 5 tails
in 10 tosses, how do the results of your tosses
compare? How about the results of your partners
tosses? How close was each set of results to what
was expected? 2. Add your results to those of
your partner to produce a total of 20 tosses.
Assuming that you expect 10 heads and 10 tails in
20 tosses, how close are these results to what
was expected? 3. If you compiled the results for
the whole class, what results would you
expect? 4. How do the expected results differ
from the observed results?
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Section 2 Answers
Interest Grabber Answers
1. Assuming that you expect 5 heads and 5 tails
in 10 tosses, how do the results of your tosses
compare? How about the results of your partners
tosses? How close was each set of results to what
was expected? Results will vary, but should be
close to 5 heads and 5 tails. 2. Add your
results to those of your partner to produce a
total of 20 tosses. Assuming that you expect 10
heads and 10 tails in 20 tosses, how close are
these results to what was expected? The results
for 20 tosses may be closer to the predicted 10
heads and 10 tails. 3. If you compiled the
results for the whole class, what results would
you expect? The results for the entire class
should be even closer to the number predicted by
the rules of probability. 4. How do the expected
results differ from the observed results? The
observed results are usually slightly different
from the expected results.
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Section Outline
Section 11-1

• 112 Probability and Punnett Squares- Mendel
  used his math background to make sense of the
  reappearance of the hidden trait.
• A.Genetics and Probability- the likelihood that a
  particular event will occur is called
  probability.
• Flip a coin once 1/2 will be heads 1/2 tails.
• Flip a coin twice 1/4 chance to have both heads.
• Flip a coin three times and the chance all will
  be heads is 1/8.

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Section Outline
Section 11-1

• Punnett Squares
• Punnett squares can be used to predict and
  compare the genetic variations that will result
  from a cross.
• Possible genetic combinations from a genetic
  cross are as follows
• Homozygous-organisms that have two identical
  alleles for a particular trait-TT or tt for tall
  or short plants.
• Heterozygous-organisms that have two different
  alleles for the same trait-Tt these are all
  hybrids.
• The traits can be measured in certain ratios.
• Phenotype-the physical trait expressed
• Genotype-the genetic makeup of the organism.

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Example

• -- If a (GgNn) plant is crossed with a (ggnn)
  plant what are the probable genotypic and
  phenotypic ratios

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GgNn x ggnn
green smooth x yellow constricted
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GgNn
g
G
n
N
GN and Gn
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GgNn x ggnn

• GN Gn

9
GgNn
g
G
n
N
gN and gn
10
GgNn x ggnn

• gN gn

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GgNn
g
G
n
N
GN and Gn
gN and gn
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GgNn x ggnn
Green smooth x yellow constricted

• GN Gn gN gn

gn gn gn gn
13
GgNn x ggnn

• GN Gn gN gn

gn gn gn gn
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• Genotypic ratio
• 4 GgNn
• 4 Ggnn
• 4 ggNn
• 4 ggnn
• 4444 or 1111.

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• Phenotypic ratio
• 4 green smooth
• 4 green constricted
• 4 yellow smooth
• 4 yellow constricted
• 4444 1111.

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Section Outline
Section 11-1

• Probability and Segregation
• Mendel predicted that three of every 4 from the
  F2 Generation would show the dominant trait and 1
  would show the recessive.

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Section Outline
Section 11-1

• Probabilities Predict Averages
• Mendels prediction was pretty close when large
  numbers of results were counted.

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Tt X Tt Cross
Section 11-2
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Tt X Tt Cross
Section 11-2