(a)[3]
Table 2.1 lists some examples of phenotypic variation in plants and animals. Complete Table 2.1 by stating whether the variation in each example is most likely caused by: genetic factors, $V_G$; environmental factors, $V_E$; or a mix of genetic and environmental factors, $V_G + V_E$.
(b)[1]
Name a spontaneous, random cellular event that can act as a source of phenotypic variation.
(c)[3]
Besides the event named in (b), describe the parts of sexual reproduction that help produce genetically different offspring.