1. Complex Inheritance and Human Heredity
Chapter 11
Complex Inheritance and Human Heredity

2. 11.1 Basic patterns of human inheritance
Main idea: The inheritance of a trait over several generations can be shown in a pedigree

3. Recessive Genetic Disorders
A recessive trait is only expressed when the individual is homozygous recessive
If the individual has at least 1 dominant allele will not express the recessive trait

4. Recessive Genetic Disorders
Carrier-an individual who is heterozygous for the recessive disorder

5. Recessive Genetic Disorders
Cystic Fibrosis- A defective gene causes a thick mucus to be produced that clogs the lungs and obstruct the pancreas
Albinism- Results in the absence of the skin pigment melanin in hair and eyes

6. Recessive Genetic Disorders
Tay-Sachs disease is a fatal genetic disorder in which harmful quantities of a fatty substance build up in tissues and the brain
Galactosemia is caused by the lack of a liver enzyme required to digest galactose, a product of lactose

7. Dominant Genetic Disorders
Some genetic disorders can be caused by dominant alleles
People unaffected would be homozygous recessive

8. Dominant Genetic Disorders
Huntingtons Disease- causes degeneration of brain cells, leads to uncontrolled movements, and loss of intellectual faculties
Achondroplasia- bone growth disorder that results in short stature

9. Pedigree
A pedigree is a diagram that traces inheritance of a trait through generations

10. Pedigree
A pedigree uses symbols to illustrate the inheritance of a trait