Vocabulary Vocabulary ReviewReview
Chapter Chapter 14 & 1514 & 15
Mendel’s true breeding
generation
P or parental generation
Alternative forms of a gene
alleles
Genetic makeup of an organism
genotype
Type of inheritance in
which hybrids are a mixture of
parental phenotypes
Incomplete dominance
Type of inheritance where
both alleles are expressed in
distinguishable ways
Codominance
Type of inheritance where
three or more genes affect the
phenotype
polygenic
Genes that tend to be inherited
together
Linked
When members of homologous pairs of chromosomes fail to separate during meiosis
Nondisjunction
Organisms that are normal but
transmit recessive alleles to offspring
Carrier
Pairs of alleles segregate
independently during meiosis
Law of Independent Assortment
Organism’s observable traits
or their appearance
Phenotype
Probability that an offspring will be heterozygous if parents are both
heterozygous
50%
When both alleles are the same for a
trait it is called this
Homozygous
AABBCC X aabbccProbability these
parents would produce AaBbCc
1 or 100%
AABbCc x AaBbCcprobability these
parents would produce AAbbCC
1/32
If two alleles at a locus differ, the dominant allele
will determine the organism’s phenotype
Law of Dominant &
Recessive Heredity
Cross determined by two traits
Dihybrid Cross
Sutton, Boveri and others were
responsible for this theory
Chromosome Theory of
Inheritance
A gene located on a sex chromosome
Sex-linked gene
Inactivated X chromosome in a
cell is called a
Barr Body
When genes are exchanged during meiosis it is called
this
Crossing-over
Plants can have multiple sets of chromosomes; a state called this
Polyploidy
When a gene is moved and joins a nonhomologous chromosome it is
called this
Translocation
An abnormal number of
chromosomes is called this
Aneuploidy
Aneuploidy where there is one extra chromosome in a
karyotype
Trisomy
Trisomy 21
Down Syndrome
What were caused in fruit flies in Thomas Hunt Morgan’s lab
Mutations
Difference in phenotype based on whether the
allele is inherited from the mother or
fatherGenomic
Imprinting
When a chromosomal
fragment is lost it is called this
Deletion
An aneuploid situation in which the organism has only one copy of a
gene
Monosomy
Probability that a heterozygous to
heterozygous dihybrid cross will
produce both dominant traits9/16
Chart showing members of a
family showing which members
show a particular trait
Pedigree