09.0 Genetics Vocab SIMPLE Review

True-breeding

Organism that produces offspring with traits identical to itself; homozygous

Allele

Different forms or "flavors" of a gene

Punnett Square

A diagram used to show potential gene combinations of offspring

Genotype

Genetic make up of an organism

Phenotype

An organism's physical characteristics, or visible traits

Homozygous

An organism that has two identical alleles for a trait; TT or tt

Heterozygous

An organism that has two different alleles for a trait; Tt

Principle of Dominance

States that some alleles are dominant and others are recessive

Law of Segregation

Mendelian law stating that two alleles for each trait separate during meiosis when gametes are made

Recessive

An allele that is NOT expressed when the dominant form of the trait is present; two alleles must be present to be expressed; tt

Dominant

Describes an allele that covers over, or dominates, another form of that trait

Probability

Likelihood that an event will occur

Gregor Mendel

"Father of Genetics"; studied inheritance of traits using pea plants

Independent assortment

Homologous chromosomes randomly line up double file on the equator during Metaphase I during meiosis when gametes are made

Genetics

The scientific study of heredity

Fertilization

Male and female gametes join during sexual reproduction to form a zygote

Hybrid

Another way to say "heterozygous"

Gametes

Sex cells (sperm and egg)

Trait

Specific characteristic that varies from one individual to another

F1 (first filial) generation

Offspring of the first parental cross

Gene

Sequence of nucleotides found on DNA that codes for a specific trait

P (parental) generation

Original generation in a genetic cross