Chapter 8 Flashcards
monohybrid cross
a genetic
cross performed to observe
the inheritance of alleles and
phenotypes for a single gene
Punnett square
a square
diagram used to predict the
genotypes of offspring
codominance
happens when
two traits are independently and
equally expressed
test cross
when an individual
expressing the dominant
phenotype but with an unknown
genotype is crossed with a
homozygous recessive individual.
The results indicate whether the
individual with the dominant
phenotype is homozygous
dominant or heterozygous
dihybrid cross
a genetic cross
used to observe the inheritance
of alleles and phenotypes for two genes
unlinked genes
genes located
on different chromosomes, or far
apart on the same chromosome.
Unlinked genes have less chance
of being inherited together
linked genes
genes that are
found close together on the same
chromosome and are likely to be
inherited together
independent assortment
the random orientation of
homologous chromosomes along
the metaphase plate during
metaphase I
crossing over
the exchange
of genetic material between
non-sister chromatids during
prophase I of meiosis, resulting
in new combinations of alleles in
daughter cells
map units
a measure of the
distance between two genes on
the same chromatid. Genes that
are closer together are more likely
to be linked genes
recombinant chromosome
a chromosome which is not
identical to one of the homologous
chromosomes in a diploid cell
parental chromosome
a chromosome which contains the
same combination of alleles as one
of the parents’ chromosomes
pedigree chart
a diagram showing
the expression of a trait over
multiple generations
consanguineous breeding
breeding of two individuals that
are closely related. Also known
as inbreeding
