Final answer:
Quantitative traits are characterized by a continuous distribution of values, are often polygenic, influenced by environmental factors, and do not fall into discrete categories.
Step-by-step explanation:
Quantitative traits are, firstly, traits showing a continuous distribution of trait values. This means they are not restricted to a set of defined categories but occur on a spectrum, with individuals showing a range of trait values that have small gradations between them. They are exemplified by features such as height, weight, or skin color in humans, all of which show a wide range of variation. Secondly, instead of being caused by alleles at a single gene, quantitative traits are often polygenic, controlled by many genes. Each of these genes may have a small additive effect on the trait, leading to the continuous variation observed. The influence of environmental factors also can't be overlooked; quantitative traits frequently show variation due to environmental effects, meaning they are not strictly genetically determined. Finally, these traits do not have values that fall into discrete, clearly separated categories. Instead, they show a range and diversity of characteristics that blend together, as opposed to traits with discontinuous variation where the traits can be distinctly categorized.