GENETICS
Apr 01, 2015
GENETICS
Gregory MENDELWHO?
Father of Genetics = Pea Plants
Independent Assortment
Genes that segregate independently, do NOT influence each other’s inheritance.
Separate genes for separate traits are passed independently of one another from parents to offspring
Dominant vs. Recessive
Traits
Dominant Recessive
Dominant Recessive
Dominant Recessive
Dominant Recessive
Dominant Recessive
Dominant Recessive
Dominant Recessive
Dominant Recessive
Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or
multiples genes.
Incomplete Dominance
Where one allele is not completely dominant over another.
Heterozygous phenotype is somewhere in between the two homozygous phenotypes.
Codominance
Both alleles contribute to the phenotype (physical characteristics).
Both alleles are FULLY EXPRESSED.
Multiple Alleles
Genes that have more than 2 alleles.
More than 2 possible alleles exist in the population.
Polygenic Traits
Traits controlled by two or more genes.
Traits that are produced by the interaction of several genes.
The FOIL method is ONLY used when finding the gametes from parents with
two traits. Use the FOIL method to find the
gametes:(RrYy)
(R + r)(Y + y). F tells you to put the FIRST of the two
traits’ alleles together.
RY
(R + r)(Y + y). O tells you to put the OUTER alleles
together.
Ry
(R + r)(Y + y). I tells you to put the INNER alleles
together.
rY
(R + r)(Y + y). L tells you to put the LAST alleles
together.
ry
Remember, FOIL reminds you to match up the:
First alleles
Outer alleles
Inner alleles
Last alleles