30 terms

(AC) Chapter 9: Fundamentals of genetics

the science of hereditary material and how traits are passed on from parent to offspring
the passing of genetic traits from parent to offspring
a genetically determined varient of a characteristic
the transfer of pollen from male reproductive structures (anthers) to the tips of female reproductive structures (pistal) of a flower
self pollination
the transfer of pollen grains from an anther to the stigma of the same flower
cross pollination
a reproductive process in which pollen from one plant is transfered to the stigma of another
true breeding
describes organisms or genotypes that are homozygous for a specific trait and thus always produce offspring that have the same phenotype for that trait
p generation
parental generation, the first 2 individuals that mate in a genetic cross
F1 generation
the first generation of offspring, offspring of P
F2 generation
the second generation of offspring, offspring of F!
describes the allele that is fully expressed when carried by only one of a pair of homologous chromosomes
describes a trait or allele that is expressed only when 2 ressesive alleles for the same characteristic are inherited
law of segregation
law that states that the pairs of homologous chromosomes seperate in meiosis so that only one chromosome from each pair is present in each gamete
law of independent assortment
law that states that genes seperate independently of one another in meiosis
molecular genetics
the study of the structures of nucleic acids and the function and regulation of genes
one of the alternative forms of a gene that governs a characteristic
the entire genetic makeup of an organism
an organisms appearence or other detectable characteristic that results from the organisms genotype and the environment
describes an individual that has identical alleles for a trait on both homologous chromosomes
describes an individual that has 2 different alleles for a trait
the likelihood that a possible future event will occur in any given instance or the envent
monohybrid cross
a cross between individuals that involves one pair of contrasting traits
punnet square
a graphic used to predict the results of a genetic cross
genotypic ratio
the ratio of the genotypes that appear in offspring
phenotipic ratio
the ratio of phenotypes produced by a cross
the crossing of an individual of unknown genotype with a homozygous recessive individual to determine the unknown genotype
complete dominance
a relationship in which one allele is completely dominant over another
incomplete dominance
a condition in which a trait is intermediate between the phenotypes of the parents. the dominat allele is not expressed fully
a condition in which both alleles for a gene are fully expressed
dihybrid cross
a cross between individuals that have the different alleles for the same gene