John and Pat are identical twins with identical DNA. John works in a movie theater, and Pat works as a lifeguard. They have very different skin pigmentation. Which is the best explanation of the difference? Skin color, a polygenic trait, is also determined by environmental factors. Skin color, a polygenic trait, is also determined by the sex of the individual. Skin color, a trait that demonstrates incomplete dominance, is also determined by environmental factors. Skin color, a trait that demonstrates incomplete dominance, is also determined by the sex of the individual.

Two students are working together on an experiment that measures the effect of different liquid fertilizers on the thickness of plants’ stems. which is most likely to result in the greatest amount of error in their scientific experiment? a.one student measures the plant stem widths by using calipers. the other student measures the widths of the same plant stems again by using a different pair of calipers. b.one student measures the plant stem widths by using calipers. the other student types the measurements as they are taken into a computer spreadsheet. c.one student weighs liquids for the experiment by using a calibrated scale. the other student weighs liquids for the experiment by using a different calibrated scale.