Alleles
Alternative forms of genes
Phenotype
An observable trait
Homozygous
An individual is ____________ for a character if the individual's two alleles for that character are the same.
Heterozygous
An individual is _____________ for a character if the indiviual's two alleles for that character are different.
Chromosome Theory of Inheritance
The ______________________ states that genes are located on chromosomes, and the behavior of chromosomes accounts for inheritance patterns
Genetic Linkage
the tendency for the alleles on one chromosome to be inherited together
Sex-Linked Genes
Any gene that is located on a sex chromosome.
Polygentic inheritance
When two or more genes affect a single character.
Punnett Square
A diagram that shows all possible outcomes of a genetic cross
Genotype
genetic makeup, or combination of alleles.
Testcross
breeding an individual of dominant phenotype with a homozygous recessive individual to determine the individual's genotype.
Codominance
inheritance pattern in which a heterozygote expresses both traits
Recessive
in a heterozygote, the allele that does not affect the trait
Dominant
in a heterozygote, the allele that does affect the trait
Dihybrid Cross
cross between organisms differing in two characters
monohybrid Cross
cross between organisms differing in only one character
Gene Locus
location of an allele on a chromosome
Genetics
is the study of heredity
Trait
a variation of a particular character
Gregor Mendel
first scientist to use experiments to investigate inheritance patterns. Used true-breeding pea plants to do this
Cross-fertilization
use sperm from one true breeding plant to fertilize the eggs of another true-breeding plant that has different traits
Hybrid
offspring of two true-breeding plants
intermediate inheritance
occurs when neither allele for a trait is dominant