There is a gene that is carried
on a chromosome and in a
diploid chromosome there is
another homologous
chromosome that has
essentially the same DNA
with the same gene for the
same trait, but they can have
slight differences (at the same
locus) that has different
ALLELES.
Deviations from Mendel's Laws
Some traits not on
nuclear chromosomes
(e.g. mitochondrial or
chloroplast chrosomes)
Traits on the same chromosome
Traits carried on
sex-chromosomes
(e.g mammals XX
female, XY male)
1859 Charles Darwin
Published "The Origin of Species"
The Garden Pea
True-breeding varities: a
particular trait was
consistently inherited
from one generation to
the next
Easy to grow
Easily distinguishable
traits (flower color,
round or wrinkled,
pod color)
2 types of fertilization
Cross mate- use
a brush to put
pollen on ovar of
another plant
Self-fertilization: take
pollen and fertilize
ovar of same plant