Human height is one of the traits that belong to traits that cannot easily be placed in discrete phenotypic classes (there is not only tall and short people, there is continuous variation of height between them). Such traits are usually controlled by more than one gene (polygenic traits).
On the other hand, a Mendelian trait is controlled by a single locus.
Answer:An increase in light intensity causes both pupils to contract (see iris) even if only one retina is directly stimulated. This is known as a consensual reflex. Conversely, a decrease in light intensity causes dilation of the pupils
