Download HEREDITY

HEREDITY
ž  Some
¡  Ex:
traits completely
Gender, Eye Color, Natural Hair Color
ž  Other
traits such as intelligence and
longevity with the influence of the
environment
ž  Our
heredity information is contained in
chromosomes
ž  Humans have 23 pairs (46 total)
ž  Half from the mother and half from the
father
ž  In other terms half come from the egg and
the other half come from the sperm
ž  Each
chromosome has thousand of genes
ž  Who discovered these?
¡  Gregor
Mendel found the laws of dominant vs
recessive genes
¡  The Laws are:
Inherited traits are determined by genes
¢  Genes occur in pairs-parent gives on of each set to
offspring
¢  Effect of a recessive gene may be masked by a
dominant gene (ex. Brown eyes are dominant over
green/blue eyes)
¢  Genes for one trait (like hair color) have NO effect on
genes of another trait (like eye color)
¢ 
ž  Genes
remain the same unless mutation
occurs
ž  How does this happen?
¡  Spontaneous
error
¡  Outside Influences
Alcohol/drug abuse
¢  Radiation
¢  Malnutrition
¢ 
ž  How
is the gender of the baby determined?
ž  The 23rd chromosome is the deciding factor
that determines the sex of a human
ž  Chromosomes 1-22 are the same for both
male and female in what they determine BUT
not the 23rd
ž  Males provide an X or Y chromosome
ž  Females provide two X chromosomes
ž  So ultimately it’s up to the guy:
¡  He
gives out a Y it’s a boy
¡  He gives out an X it’s a girl
ž  Males
have a greater chance of inheriting
colorblindness
ž  Females are carriers for hemophilia (blood
disease) because the disease is carried on
the X chromosome, however males are more
likely to contract the disease because the
healthly X masks the infected X and guys only
have one X chromosome
ž  Blood
Types
¡  O:
it’s the most common, so they are the
universal donor
¡  AB: it’s the least common, so they are the
universal reciever
ž  RH
Factor: Proteins on red blood cells.
You’re either RH negative (you don’t have
the protein) or you’re RH positive