1. Human Genetic Traits ? ABC news – video clip thehappyhospitalist.blogspot.com/2008_10_01_a... http://www.telegraph.co.uk/news/worldnews/asia/indonesia/tree-man/

2. Dominant and Recessive Traits Dominant traits are seen in the phenotype for both Heterozygous (Tt) and Homozygous (TT) genotypes. Dominant Examples: Tongue-roller Freckles High blood pressure Dwarfism Six fingers Baldness (males) Dimples Recessive traits are seen in the phenotype ONLY When a person has a Homozygous (tt) genotype.

3. Genetic Diseases Dominant (TT or Tt) Huntington’s Recessive (tt) Tay-Sachs PKU Cystic Fibrosis Sickle-cell Anemia Sex-Linked Recessive (X r Y) or (X r X r ) Hemophilia Color blindness

4. Other Inherited Diseases Down Syndrome (3 copies of chromosome 21) Nondisjunction

5. Examples of Diseases which are NOT Inherited Infectious Diseases Chickenpox Flu Strep throat Food poisoning Cancer Some cancers are due MOSTLY to environmental exposure Some cancers have a genetic risk factor Diet Some diseases are caused by a lack of nutrients like vitamin C