Genetics Through the Ages

By: KellyJohn Murray

What is the study of genetics?

Genetics is the study of heredity. Heredity is a biological process where a parent passes certain genes onto their children or offspring.

Who discovered Genetics and how did he do this?

Gregor Mende discovered genetics. He studied pea plants and made two important innovations to the genetics community. *Developed pure lines*Counted his results and kept statistical notes

Dominant Allele

An allele that produces the same phenotype whether its paired allele is identical or different

Recessive Allele

An allele that produces its characteristic phenotype only when its paired allele is identical

Heterozygous

Two different alleles for a trait.

Homozygous

Two identical alleles for the same trait

Genotype

The genetic constructution of an individual organism.

Phenotype

The physical attributes of an organism

Simple Punnett Square cross

*Genotype: Yy=50% yy=50%*Phenotype: Yellow pod=50% Green pod=50%

Incomplete Dominance

The phenotype of a plant is taken from both parents equally. A white and red flower combining to create a pink flower is an exelent example of incomplete dominance.

Codominance

Both alleles are expressed eqaually. An example would be spotted cows.

Multiple Alleles and their uses

Multiple alleles are an inheritence pattern. Multiple alleles are used to determine blood types. An example is Type A blood who's genotype is iAi.

Sex-linked Traits

Sex linked traits are the phenotypic expression of an allele related to the chromosomal sex of an individual. Hemophillia is an example of sex-linked traits.