For Concepts of Genetics By Robert Brooker Updated 2026

Genetics Concepts by Robert Brooker Updated 2026 | Detailed Correct Solutions transmission genetics - answer - the field of genetics concerned with heredity and the mechanisms by which genes are transferred from parent to offspring trait - answer - any detectable phenotypic variation of a particular inherited character monohybrid cross - answer - a genetic cross only involving one character (ex: AA x aa); This is made by mating true-breeding individuals from two parent strains, each exhibiting one of the two contrasting forms of the character under study selfing - answer - in plant genetics, the fertilization of a plant's ovules by pollen produced by the same plant. F1 (first filial) generation - answer - progeny resulting from the first cross in a series F2 (second filial) generation - answer - progeny resulting from a cross of the F1 generation reciprocal cross - answer - a pair of crosses in which the genotype of the female in one is present as the genotype of the male in the other and vice versa. segregation - answer - the separation of maternal and paternal homologs of each homologous chromosome pair into gametes during meiosis phenotype - answer - the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment. gene - answer - A segment of DNA on a chromosome that codes for a specific trait allele - answer - An alternative form of a gene. genotype - answer - genetic makeup of an organism Homozygous - answer - an individual with identical alleles for a gene or genes of interest. These individual will produce identical gametes (with respect to the gene or genes in question) and will therefore breed true. heterozygous - answer - an individual with different alleles at one or more loci. Such individuals will produce unlike gametes and therefore will not breed true testcross - answer - a cross between an individual whose genotype at one or more loci may be unknown and an individual who is homozygous recessive for the gene or genes in question dihybrid cross - answer - a genetic cross involving two characters in which the parents possess different forms of each character (ex. yellow, round x green, wrinkled) dihybrid cross ratio - answer - 9:3:3:1 phenotypic ratio independent assortment - answer - Independent segregation of genes during the formation of gametes diploid (2n) - answer - a condition in which each chromosome exists in pairs; having two of each chromosome locus - answer - the site or place on a chromosome where a particular gene is located pedigree - answer - in human genetics, a diagram showing the ancestral relationships and transmission of genetic traits over several generations in a family. proband (p) - answer - an individual who is the focus of a genetic study leading to the construction of a pedigree tracking the inheritance of a genetically determined trait of interest How to determine the number of different types of gametes formed. - answer - 2^n (where n is the number of heterozygous gene pairs) How to determine the number of different types of genotypes produced. - answer - 3^n (where n is the number of heterozygous gene pairs) How to determine the number of different types of phenotypes produced. - answer - 2^n (where n is the number of heterozygous gene pairs) Gregor Mendel - answer - Augustinian monk and botanist whose experiments in breeding garden peas led to his eventual recognition as founder of the science of genetics () monohybrid cross ratio - answer - 3:1 phenotype 1:2:1 genotype trihybrid cross ratio - answer - 27:9:9:9:3:3:3:1 Unit Factors in Pairs - answer - Mendel's postulate: genetic characters are controlled by unit factors received from parents (each diploid individual receives one factor from each parent) Dominance/Recessiveness - answer - Mendel's postulate: when two unlike unit factors responsible for a single character are present in a single individual, either expressed or not expresse