Question | Answer |
Heredity | the transmission of traits (inherited features) from one generation to the next |
Genetics | the scientific study of heredity; began with the work of Gregor Mendel in the 19th century |
Character | a heritable feature that varies among individuals within a population |
Trait | a variant of a character found within a population |
Self-Fertilize | a form of reproduction that involves fusion of sperm and egg produced by the same individual organism |
Cross-Fertilization | the fusion of sperm and egg derived from two different individuals |
True-Breeding | referring to organisms for which sexual reproduction produces offspring with inherited traits identical to those of the parents |
Hybrid | an offspring of parents of two different species or two different varieties of one species |
P Generation | the parent individuals from which offspring are derived in studies of inheritance |
Monohybrid Cross | an experimental mating of individuals differing in a single character |
Homozygous | having two identical alleles for a given gene |
Heterozygous | having two different alleles for a given gene |
Dominant Allele | the allele that determines the phenotype of a gene when the individual is heterozygous for that gene |
Recessive Allele | an allele that has no noticeable effect on the phenotype of a gene when the individual is heterozygous for that gene |
Law of Segregation | a general rule in inheritance that individuals have two alleles for each gene and that when gametes form by meiosis, the two alleles separate, each resulting gamete ending up with only one allele of each gene |
Punnett Square | a diagram used in the study of inheritance to show the results of random fertilization |
Phenotype | the expressed traits of an organism |
Genotype | the genetic makeup of an organism |
Locus | the particular site where a gene is found on a chromosome |
Dihybrid Cross | an experimental mating of individuals differing in two characters |
Law of Independent Assortment | a general rule of inheritance that when gametes form during meiosis, each pair of alleles for a particular characteristic segregate independently of other pairs |
Rule of Multiplication | a rule stating that the probability of a compound event is the product of the separate probabilities of the independent events |
Rule of Addition | a rule stating that the probability that an event can occur in two or more alternative ways is the sum of the separate probabilities of the different ways |
Wild-Type Trait | the version of a character that most commonly occurs in nature |
Pedigree | a family genetic tree representing the occurrence of heritable traits in parents and offspring across a number of generations |
Carrier | an individual who is heterozygous for a recessively inherited disorder and who therefore does not show symptoms of that disorder but who may pass on the recessive allele to offspring |
Complete Dominance | a type of inheritance in which the phenotypes of the heterozygote and dominant homozygote are indistinguishable |
Incomplete Dominance | a type of inheritance in which the phenotype of a heterozygote is intermediate between the phenotypes of the two types of homozygotes |
Codominant | inheritance pattern in which a heterozygote expresses the distinct trait of both alleles |
Pleiotropy | the control of more than one phenotypic characteristic by a single gene |
Polygenic Inheritance | the additive effects of two or more gene loci on a single phenotypic characteristic |
Linked Genes | genes located near each other on the same chromosome that tend to be inherited together |
Recombination Frequency | with respect to two given genes, the number of recombinant progeny from a mating divided by the total number of progeny |
Sex-Linked Gene | a gene located on a sex chromosome |