Inherited Characteristics Heredity affects almost every aspect of your life. It controls some traits completely. It works with your environment in determining other traits like intelligence and longevity.

Determination of Sex Genetic material passed on by father determines the sex/gender of a baby. –Autosomes – first 22nd pair of chromosomes –The 23 rd pair of chromosomes are the sex chromosomes. –XX = girl –XY = boy

Sex-linked Characteristics Sex-linked characteristics are characteristics that are determined by genes on the X chromosome. Color blindness – the inability to distinguish colors, usually red and green. About 8% of males in the United States are color blind. Hemophilia – a bleeding disorder in which blood clots very slowly

Intellectual Ability Intellectual potential is inherited but your environment and response to environment affect it greatly. IQ – Intelligence Quotient is obtained by dividing mental age / chronological age. 90 – 110 = normal 140+ = genius

Blood Factors Two important blood factors are determined by heredity. They are blood type and the RH factor

A persons specific blood type is determined by genes A – 40% B – 10 % O – 42% of people in U.S. They are universal donors. AB – universal receivers 8% of people in U.S. The Rh factor is a specific blood element. People who inherited it are Rh+ People who did not are Rh- About 85% of Caucasion race is Rh+ Other races are almost 100%+

Rh factor The Rh factor creates a problem only when an Rh- mother is carrying a baby who has received the Rh+ from the father. During pregnancy and childbirth, some of the babys blood cells may enter the mothers bloodstream. The mother then produces antibodies to counteract this factor. This seldom creates a problem with the first child, but the antibodies can attack future babies red blood cells causing jaundice, anemia, and possibly stillbirth. Today Rh- mothers are given a vaccine after the birth of each child to neutralize any Rh+ blood cells to prevent her body from making antibodies.

Longevity If your relatives tended to live long lives, you may inherit that tendency. Average life expectancy of early colonists was 35, now it is more than 70. Women live longer than men. More males are born, but more males die during childhood. More men die at a younger age.