genetics 1 ruder

GeneticsThe field of biology devoted to understanding heredity, how

characteristics are transmitted from parents to offspring.

Gregor Mendel

• Entered monastery in Brunn, Austria at age of 21 in 1842.

• Assigned task of tending the garden.• 1851 entered the University of Vienna to

study science and mathematics (Statistics).• Returned to monastery to teach high school

and kept a garden plot where he grew garden peas , Pisum sativum.

• Considered the father of genetics.

Mendel observed 7 characteristics each with 2 contrasting traits.

Important vocabulary for understanding Mendel’s experiments.• Pollination = plant reproduction

anthers/stamens(male) stigma/carpel(female)• Self-pollination vs. cross-pollination• Mendel controlled pollination by removing

anthers.• Pure – ALWAYS produce offspring with a

particular trait (14 total for the pea plants he observed).

Mendel’s Experiments

Mendel’s Results and Conclusions

• Recessive and Dominant Traits• Law of Segregation• Law of Independent Assortment

Recessive and Dominant Traits

• Recessive Factor – lower case• Dominant Factor – upper case• Factors are now called Alleles.

Law of Segregation

• A pair of factors is segregated, or separated, during the formation of gametes.

Law of Independent Assortment

• Factors for different characteristics are distributed to gametes independently.

More Vocabulary

• Genotype – genetic make-up of an organism. Pp• Phenotype – physical appearance of an org. Purple• Homozygous – both alleles of a pair are alike: PP, pp, both dominant or both recessive. (Pure)• Heterozygous – Alleles of a pair are different: Pp, one dominant and one recessive. (Hybrid)