1. Patterns of Inheritance

2. 1. Polygenic traits -Traits controlled by many genes ex. Skin color: 6 genes control the amount of melanin produced more melanin means darker skin color

3. 2. Complex Characters- traits affected by the environment as well as genetics Exposure to sunlight : skin color Nutrition: Height, Diabetes, Heart disease Soil type: Hydrangea flowers are blue if grown in acidic soil

4. 3. Multiple Allele Traits Ex: Human Blood types Alleles : A, B, O

5. 4. Sex linked Traits – on the x chromosome Ex: colorblindness Hemophilia

6. 6. Sex influenced traits- influenced by sex hormones Ex: baldness – influenced by testosterone dominant in men recessive in women

7. 7. Incomplete Dominance Ex: Sickle Cell Trait Point mutation on chromosome 11 causes improperly formed hemoglobin. This causes sickle shaped red blood cells which cannot carry oxygen properly and may clog capillaries

9. Genotypephenotype SS Normal red blood cells AAHas sickle cell disease ASis a carrier of sickle cell, has few symptoms, is resistant to malaria

12. symptoms Pain in legs, elsewhere Weakness Fatigue may lead to tissue and organ damage