Gregor Mendel is the father of modern genetics

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Gregor Mendel is the father of modern genetics. For 14 years he studied the

Gregor Mendel is the father of modern genetics. For 14 years he studied the inherited characteristics of garden peas.

Mendel picked common garden pea plants because they can be grown easily in large

Mendel picked common garden pea plants because they can be grown easily in large numbers and their reproduction can be manipulated.

Flowers of pea plants have both male and female reproductive organs.

Flowers of pea plants have both male and female reproductive organs.

Mendel chose 7 traits to study. Trait- a specific characteristic such as color or

Mendel chose 7 traits to study. Trait- a specific characteristic such as color or height.

Mendel chose 7 traits. Trait- a specific characteristic such as color or height. Traits

Mendel chose 7 traits. Trait- a specific characteristic such as color or height. Traits are determined by inherited genes

Genes have different forms called alleles Ex. For height: Allele for tall Allele for

Genes have different forms called alleles Ex. For height: Allele for tall Allele for short

Dominant Allele – the trait that is always exhibited if allele is present

Dominant Allele – the trait that is always exhibited if allele is present

Dominant Allele – the trait that is always exhibited if allele is present Recessive

Dominant Allele – the trait that is always exhibited if allele is present Recessive allele – the trait that is only exhibited if dominant allele is not present

Traits Mendel studied Dominant Recessive

Traits Mendel studied Dominant Recessive

Traits Mendel studied Dominant Recessive

Traits Mendel studied Dominant Recessive

Trait Dominant Recessive Seed Form Round (R) Wrinkled ( r) Seed Color Yellow (Y)

Trait Dominant Recessive Seed Form Round (R) Wrinkled ( r) Seed Color Yellow (Y) Green (y) Pod form Inflated (V) Restricted (v) Pod color Green (G) Yellow (g) Flower Position Axial (F) Terminal (f) Seed Coat Color Gray (A) White (a) Stem Length Tall (T) Short (t)

Each plant has two alleles for each trait – One from each parent

Each plant has two alleles for each trait – One from each parent

Each plant has two alleles for each trait – One from each parent Homozygous

Each plant has two alleles for each trait – One from each parent Homozygous – the alleles are the same form. (Ex: TT or tt)

Each plant has two alleles for each trait – One from each parent Homozygous

Each plant has two alleles for each trait – One from each parent Homozygous – the alleles are the same form. (Ex: TT or tt) Heterozygous – the alleles are a different form ( Ex: Tt)

Genotype: What allele forms are present. Ex: TT, Tt, tt Phenotype: What does it

Genotype: What allele forms are present. Ex: TT, Tt, tt Phenotype: What does it look like? Ex: Tall or short?

Phenotype Ex: Tall or short? TT – Tall tt - short Tt - Tall

Phenotype Ex: Tall or short? TT – Tall tt - short Tt - Tall

Allele combinations can be determined by Punnett squares Example: Flower color Purple (P) is

Allele combinations can be determined by Punnett squares Example: Flower color Purple (P) is dominant White (p) is recessive

Using a Punnett Square White Flower Parent (pp) Purple Flower Parent (PP) P p

Using a Punnett Square White Flower Parent (pp) Purple Flower Parent (PP) P p p Pp Pp Pp

Cross heterozygotes – Flower color

Cross heterozygotes – Flower color

Cross heterozygote with homozygous recessive

Cross heterozygote with homozygous recessive