Genotypes & Phenotypes

Paula Meneses & Joshua Aguilar

Genotypes

Dominant/Recessive Alleles. Inheritable information. Contribute to your

Phenotypes. Polygenic Traits & Single

Gene Traits. Cell → Nucleus →

Chromosomes → DNA Strands → Genes (Made up of Alleles.)

Homozygous Heterozygous

Two same alleles Two different alleles

Phenotypes

Based on your Genotypes. 25% Chance of Peak & 75% of no Peak.

Are all your physical traits. Can be Skin Color, Hair Color, Eye Color, Eye

Shape, etc..

B b

B BB Bb

b Bb bb

No Widows Peak: B (Big B)

Widows Peak: b (Little b)

Dominant & Recessive Genes

Dominant Alleles are more likely to influence the Phenotype.

Recessive Alleles are less likely to influence the Phenotype.

Genotypes can be passed on.

If Recessive Gene isn't physically viewable, it will be passed on to offspring.

If heterozygous, Recessive Gene can still be passed on.

Variation of Genetic Info

In a community, the genetic information combined is a Gene Pool...

Gene Mutations can occur..

Genetic Shuffling also occurs..

Crossing Over can occur..

Polygenic & Single Gene Traits

Polygenic Traits: Controlled by more than one gene.

Example: Eyes, Skin, Hair, Height, Ears, Nose, Lips, etc.

Single Gene Traits: Controlled by one gene. You have it or not.

Example: Widows Peak, Earlobes, Ability to Roll Tongue, PTC Tasters, Hair on Knuckles, etc.

Genetic Code

Genotypes are written in a Genetic Code.

Consists of a sequence of Codons

Example of a Codon: “AUG” (Methionine)

Each Codon will stand for a single amino acid.