Additive trait and dihybrid cross (1:4:6:4:1 ratio)

Quantitative trait Additive genes are those genes that code for the same trait and their effects work together on the phenotype. An example of a function of additive genes is on the eye colour. ... Additive genes affect the same trait. That is when the dominant forms of both genes are present together and produce double effect. Dihybrid cross is a cross between two individuals who differ in two observed traits that are controlled by two distinct genes. If the two parents are homozygous for both genes, then the F1 generation of offspring will be uniformly heterozygous for both genes and will display the dominant phenotype for both traits. In genetics, the phenotype is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. The genotype of an organism is its complete set of genetic material. Genotype can also be used to refer to the alleles or variants an individual carries in a particular gene or genetic location. Keywords: Seed weight in a particular plant species is determined by pairs of alleles at two loci (a+ a- and b+ b-) that are additive and equal in their effects. Plants with genotype a- a- b- b- have seeds that average 1.6 g in weight, whereas plants with genotype a+ a+ b+ b+ have seeds that average 4 g in weight. A plant with genotype a- a- b- b- is crossed with a plant of genotype a+ a+ b+ b+. 1. What is the predicted weight of seeds from the F1 progeny of this cross? 2. If the F1 plants are intercrossed, what are the expected seed weights and proportions of the F2 plants? #dihybridCross #additiveTrait #quantitativeTrait #Genetics #phenotype #genotype #Allele #gene