Describe4 marksStandard
In a population of riverbank sunflowers, researchers studied two traits: the number of petals per flower (either 5 or 6) and the height of plants measured in centimetres (range 30–120 cm). The petal number is controlled by a single gene with two alleles, while height is influenced by many genes. Soil moisture varies across the riverbank, and taller plants tend to be found in wetter areas. Describe the variation shown by each trait in terms of discontinuous and continuous variation, and explain the contributions of genetic and environmental factors. Also describe how a t-test could be used to determine whether soil moisture significantly affects plant height.