Transcript Section 1 Mendel and His Peas Chapter C3

Chapter C3
Section 1 Mendel and His Peas
Gregor Mendel: Who was he?
Priest/monk and a scientist/teacher
• He worked in the monastery garden.
• Did research on pea plants
• 150 years ago He discovered the
principles of heredity
•
+ ½ each = 2 pts
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Chapter C3
Section 1 Mendel and His Peas
+ 1 each = 2 pts
Mendel’s Research
• Mendel studied only
one characteristic at a
time.
• He studied pea
plants because they
•Grow quickly
•Self-pollinate
•have simple traits
with few variations.
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Chapter C3
Section 1 Mendel and His Peas
Unraveling the Mystery
Mendel was careful to use plants that were true
breeding for each of the traits he was studying. By
doing so, he would know what to expect if his plants
were to self-pollinate.
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Chapter C3
Section 1 Mendel and His Peas
Pea Plant Experiments:
What were his results?
Mendel’s
1st
Experiments
+ 1 each = 3 pts
• The trait of only ONE parent appeared in
the first generation.
•the trait that appeared =dominant trait.
•The trait that seemed to disappear =
recessive trait.
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Chapter C3
Section 1 Mendel and His Peas
Mendel’s 2nd Experiments
• Mendel allowed the first-
generation plants to selfpollinate.
• In second-generation,
MOST plants had the
dominant trait and some
had the recessive trait.
+ 1 each = 2 pts
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Chapter C3
Section 1 Mendel and His Peas
The ratio between dominant & recessive traits
The ratio was
always about
3:1
(dominant :
recessive)
+ 1 pts
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Chapter C3
Section 1 Mendel and His Peas
What conclusions did he make?
• His results could only be explained if each plant had
two sets of instructions for each characteristic.
• each parent donated one set of instructions
+ 1 each = 2 pts
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Chapter C3
Section 1 Mendel and His Peas
30 Years after Mendel’s death:
• his research was rediscovered
• his work opened the door to modern genetics
• he is called the “Father of Genetics”
+ 1 each = 3 pts
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Biology
• The area of science that studies living
organisms.
–“bio” = life/ living
–“ology” = the study of
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Genetics
• The area of science that studies
heredity.
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Heredity – p. 56
• The passing of traits from parents
to offspring.
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Characteristic – p. 58
• A feature that has different forms
in a population.
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Characteristics vs. Traits
Characteristics
Traits
Blonde
Traits
Brown
Hair Color
Traits
Black
Traits – p. 59
• A genetically determined form of
a characteristic.
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Dominant Trait-- p. 59
• The trait observed in the first
generation when parents that have
different traits are bred.
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Recessive Trait –p. 59
• A trait that reappears in the
second generation after
disappearing in the first
generation when parents with
different traits are bred.
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