Mendelian Genetics

What are mendelian genetics?

By definition: A set of theories that attempts to explain inheritance and biological diversity according to the tenets of Gregor Mendel regarding the transmission of genetic characters from parent organisms to their offspring based on his statistical analysis and scientific breeding experiments on pea plants. His significant contributions served as the cornerstone of genetics.

Mendel's First Law of Genetics (Law of Segregation)

Mendel made two innovations to the science of genetics:

He developed pure lines

He counted his results and kept statistical notes

Pure Line - a population that breeds true for a particular trait [this was an important innovation because any non-pure (segregating) generation would and did confuse the results of genetic experiments]

Who was Mendel?

Austrian man named Gregor Mendel was particularly important to understanding biological inheritance. Mendel studied different pea plant traits.

Explain what is genotype and phenotype, homozygous and heterozygous, alleles.

Genotype is the percentage of genes and how they appear (genetically) in the offspring. For example, 25% yy 50 % Yy 25% YY

Phenotype is the percentage of how the offspring will look physically. For example 75% Yellow, 25% Green.

Homozygous: Organisms that have two identical alleles for a particular trait. (YY)

Heterozygous: Organisms that have two different alleles for the same trait. (Yy)

Alleles: Different forms of a gene.

In this lab activity you have to search and explain how it works genetically speaking the color of the eyes in human beings. explain and use the punnet squares to give an example.

Brown eyes= B (Dominant)

Blue eyes= b (Recessive)

Let’s say the father has blue phenotype, which would mean he has homozygous genes (bb), the mother has brown eyes, although she has a genotype of Bb.

This means that 50% of the offspring’s phenotype would be brown eyes and its genotype would be Bb.

The other 50% would have blue eyes and a genotype of bb.

http://www.ndsu.edu/pubweb/~mcclean/plsc431/mendel/mendel1.htm

...