2.  Most traits are neither harmful or helpful ◦ Ex. Blood type – there is no advantage or disadvantage to having A or B blood type  Some are helpful ◦ Ex. Coloration on an animal  Mimicry  Camouflage  Some are harmful ◦ Ex. Health risks

3.  Autosomal traits – carried on autosomes ◦ 22 pairs of autosomes ◦ 1 pair of sex chromosomes  X and Y

4.  Some diseases are genetic (passed down from one generation to the next)  Many inherited diseases result from mutations ◦ What is a mutation?  Most are autosomal ◦ Cystic fibrosis ◦ Huntington disease ◦ Sickle cell  Others on sex chromosomes

5.  Disease affecting sweat and mucous glands  Chloride ions outside of cells lead to problems maintaining salt balance  Affects lungs – thicker and stickier mucous ◦ Difficulty breathing ◦ Supports bacterial growth  Also affects pancreas, liver, and sex organs  Autosomal recessive http://www.youtube. com/watch?v=L10W9 MdRjPs

6.  Degenerative disease of the nervous system  Progressive – worse over time ◦ Eventually breaks down nerves in the brain  Causes: ◦ Uncontrollable movements ◦ Mental deterioration ◦ Premature death  Autosomal DOMINANT  Generally has late onset http://www.youtube.com/watch?v=MR ZoM5L5dak

7.  Changes in hemoglobin (a protein in blood)  Red blood cells fold into a sickle shape  Problems: ◦ blockages in blood flow ◦ Weakness and pain ◦ Damanges brain, heart and spleen  Can be fatal  Autosomal recessive  Incomplete dominance  1 allele means you have the sickle cell trait  Increases chances of surviving malaria

9.  Unable to produce normal clotting protein  Bruise easily  Can die from minor cuts – can’t stop bleeding  Commonly sex linked trait  Occurs mostly in what gender? http://www.youtube.com/watch?v=uhy D0vdQDZs

10.  Behavior or certain substances can affect the expression of a gene  Heart disease and diabetes ◦ Genetic component accelerated by diet and exercise  Skin cancer ◦ UV rays strongly related to skin cancer but a higher risk in fair skin and light hair and eyes

11.  Chart or family tree, that traces the inheritance of a trait  Carriers have one copy of each gene

12.  Horizontal lines indicate marriage or parentage  Vertical lines are children  Generations are numbered  People are numbered  Males = squares  Females = circles  Solid = affected  Blank = unaffected