2. Gregor Johann Mendel
(1822-1884)
• Born on -22 July,1822
• Birth place -Austria
• Studied philosphy for several
years
• Join the Augustinian monastery
in Sep.1843
• Joined the University of Vienna
from 1851- 53
• Returned to Brno to teach
Physics and Natural Sciences.
3. Experiments on pea plant
Conducted breeding experiments
on pea plant
Experiment period- 1856-1863
Presented his result- in 1865 at
the meetings of the Brno Natural
Science Society
Paper publision- 1866
4. Throughout life he not get any
recognition for his work
Died on – 6 Jan. 1884 (61 years age)
His discovery was unappreciated
until 1900
3 Botanist-Hugo de Vries(Holland),
Erich Von
Tshermak(Germany),Karl
Correns(Austria)
Now it is called as ‘ Mendel’s law of
7. Mono and Dihybrid crosses
and Mendel’s laws
Dihybrid
cross
Monohybrid
cross
Laws
Based on
Law of
Segregation
Law of
Independent
Assortment
Law of
Dominance
8. 1. LAW OF DOMINANCE
In heterozygous condition
recessive alleles will
always be masked by
dominant alleles.
9.
10. 2. LAW OF SEGREGATION
Alleles pair separate or
segregate during gamete
formation and randomly
reunite at fertilization.
11.
12. 3. LAW OF INDEPENDENT
ASSORTMENT
The 2 allele of each character
assort independent of the allele of
other character at the time of
gamete formation and get
randomly rearranged in the
offspring.
13.
14. Reasons for Mendel’s success
1. Understand the reasons for
failure of earlier workers.
2. Study of inheritance of only one pair
of contrasting character at a time.
15. 3. His choice of experimental subject
I.e, Pisum sativum.
Plant is easy to cultivate
Need small space
Grow relatively rapidly
Produces many offsprings which have easily
countable traits
Having characters with two easily
distinguishable contrasting forms
16. Having perfect flowers
Flowers are ordinarily self fertilized
4. He avoided characteristics that display a range
of variation.
5. He adopted an experimental approach.
6. He used the scientific method.
7. He kept careful record of the number of
progeny.
