mendel concept of genetics

MENDEL CONCEPT OF GENETICS

Presented by – VARSHA JAIN

Gregor Johann Mendel (1822-1884)

He proposed law of inheritance

Mendelian Genetics:

Gregor Johann Mendel (1822-1884)

Augustinian monk, Czech Republic.

Foundation of modern genetics.

Studied of the garden pea (Pisum sativum) beginning in 1854.

Published his theory of inheritance in 1865 - “Experiments in Plant Hybridization”

Mendel was “rediscovered” in 1902.

Gregor Johann MendelBetween 1856 and 1863, Mendel cultivated and tested some 28,000 pea plantsHe found that the plants' offspring retained traits of the parentsCalled the “Father of Genetics"

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Mendel’s Hypotheses

Mendel analyzed that something had to be transmitted across the generations of an organism that allowed observable characteristics to carry on to next generation.

He developed a simple theory to explain the transmission of hereditary trait.

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Mendel stated that physical traits are inherited as “particles”Mendel did not know that the “particles” were actually Chromosomes & DNA

Particulate Inheritance

Mendel’s Pea Plant Experiments

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MENDEL EXPERIMENT

Mendel was the first biologist to use Mathematics – to explain his results quantitatively.

Mendel predictedThe concept of genesthat occur in pairs and

one gene of each pair ispresent in the gametes

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Punnet square

first used by reginald c. punnet.

A chart that allow us to determine that different genotype that offspring can inherit from their parent.

Mendel’s Hybridization Experiments

2010 Pearson Education, Inc.

Main Reason Behind Mendel Success

Any one trait at a time.

Specific aim.

Maintain records in crosses

Use statistical and mathematical principle

Law of dominance- In a cross of parents that are pure

contrasting traits, only one form of the trait will appear in the next generation.

All the offspring will be heterozygous and express only the dominant trait.

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Law of segregation-

The two members of a gene pair (allele) segregate (separate) from each other in the formation of gamete , half the gamete carry one allele, and the other half carry the other allele.

Law of independent assortment-

“When the two pair of traits are combined in hybrid, segregation of one pair of character is independent of the other pair of characters.”

Rediscovery of Mendel’s WorkThree botanists, Hugo de Vries, Erich von Tschermak, and Carl Correns, independently rediscovered Mendel and his work in other plant species in 1900.

Genetics was born !