Transcript mendel and genetics

Gregor Mendel
1822-1884
The Monk Who
Studied Pea
Plants
First person to trace
the characteristics of
successive generations
of living things
 He was an Augustinian monk who taught natural
science and math to high school students.

Second child of Anton and Rosine Mendel
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They were farmers in Brunn, Czechoslovakia
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They couldn’t afford for him to attend college
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Gregor Mendel then attended the Augustinian
Monastery and became a monk
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He was later sent to
the University of
Vienna to study.

Mendel was inspired
to study variance in
plants by his
professors and
colleagues
Gregor J. Mendel, O.S.A., experimental
garden (35x7 meters) in the grounds of
the Augustinian Monastery in Old
Brno.Its appearance before 1922.
Courtesy of Villanova University
Archives.
The Monastery Garden with the
greenhouse which
Gregor J. Mendel, O.S.A., had built in
1870. Its appearance before
1902.Courtesy of Villanova University
Archives.
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Mendel studied the variances in
traits displayed by pea plants
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The traits observed included
seed shape, seed color, flower
color, and height.
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He realized that the instructions
for plant traits must be carried in
an organism’s genetic material
Mendel’s Experiments

He took the male pollen
from one plant and
fertilized the female plant
to cross traits (combine
genetic material) .

After the seeds grew, he
planted them to see what
traits would appear in the
next generation.
“P
Generation”
“F1 Generation”
Mendel’s Results
He took a purebred
green seeded plant
and crossed with a
purebred yellow
seeded plant.
100% of the F1
always had
yellow seeds!
F2 always had
a 3:1 ratio!
Y= Yellow allele
P Generation =
Parents
F1 Generation=
First Filial (means
first son in Latin)
F2 Generation=
Second Filial
Mendel realized that traits are inherited in numerical ratios!
Mendel’s Conclusions
Y= Yellow allele
•He realized that each trait is controlled by two genes.
•He called this pair of genes that code for the same trait alleles.
•He realized that each plant inherits half of their genes from each
parent.
•He called the trait that always showed up in the next generation the
dominant trait (represented with a capital letter)
•He called the trait that seemed to hide in the next generation the
recessive trait (represented with a lower case letter)
Mendel’s Findings
Applied
Y= yellow allele (Dominant Trait)
YY= Yellow Purebreed
yy= Green Purebreed
Yy= Yellow Hybird
y= green allele (Recessive Trait)
P Generation
YY
yy
F1 Generation
Yy
F2 Generation
YY
Yy
Yy
Yy
Yy
yy
Yy
From his studies, Mendel derived certain basic laws of
heredity:
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Hereditary factors do not combine, but are passed
intact
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Each member of the parental generation transmits
only half of its hereditary factors to each offspring
(with certain factors "dominant" over others)
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Different offspring of the same parents receive
different sets of hereditary factors.
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Mendel’s works became the
foundation of modern
genetics
He later also crossed mice
His love of nature encouraged
his interest in research
Also interested in
meteorology and theories of
evolution
It took seven years to prove
laws of inheritance