Chapter 9 Flashcards
Genetics
The study of genes and genomes
Allele
Alternative form of a gene
Heredity
The passing on of traits from parents to offspring
Gregor Mendel
Father of genetics, pea plant experiment
Law of Independent Assortment
Factors for different characteristics are distributed to gametes independently
Law of Dominant and Recessive
A trait controlled by a recessive factor has no observable effect on an organisms appearance when it is paired with a dominant trait
Law of Segregation
A pair of factors is separated during the formation of gametes
P1 generation
Parental generation
Pollination
Pollen grains produced in the anthers(male) are transferred to the stigma(female)
Self pollination
Pollen is transferred from the anthers of a flower to the stigma of either the same flower or a flower on the same plant
Cross pollination
Transfer of pollen between two different plants
Purebred
Homozygous
True-breeding
Displaying only one form of a particular trait in offspring
Dominant
Genetic trait that is expressed when it’s allele is homozygous dominant or heterozygous
Recessive
Genetic trait that is not expressed when the contrasting form of the trait is present
Trait
Characteristic
Punnett Square
A diagram to predict the probability that certain traits will be inherited by offspring
Dihybrid cross
2 traits
Monohybrid cross
1 trait
Gene
Short segment of a chromosome, unit of hereditary information
Heterozygous
Hh
Homozygous
HH or hh
Phenotype
The appearance of an organism based on it’s genotype
Genotype
The genetic makeup of an organism
Test cross
A genetic cross of two individuals where one individual has a known phenotype but unknown genotype
Hybrid
Heterozygous
Probability
The likelihood a specific event will occur
Genotypic ratio
The ratio of the genotype that appear in offspring
Phenotypic ratio
The ratio of the phenotypes that appear in offspring
Incomplete dominance
Two or more alleles influence the phenotype, resulting in a phenotype intermediate between the two parents
Codominance
Both alleles for a gene are expressed in heterozygous offspring
Progeny
Offspring of the offspring, also called filial generations
Autosome
Not a sex chromosome
