Final answer:
The autonomous (Ac) and non-autonomous (Ds) elements in maize do not work together if the Ac element is missing or inactive, resulting in non-functioning Ds elements and a lack of expected variegation in the maize kernels.
Step-by-step explanation:
In maize, the autonomous and non-autonomous elements that do not work together are the Activator (Ac) and Dissociation (Ds) systems described by Barbara McClintock. The Ds element is a non-autonomous transposable element that is unable to cause chromosomal breakage without the presence of the Ac element, which is an autonomous transposable element. McClintock's experiments showed that when she crossed a homozygous dominant male with a homozygous recessive female from a different breeding stock, the expected variegated pattern of maize kernels was not observed because the Ac element was missing or inactive in the female's new breeding stock, rendering the Ds element non-functional. Further implications of her research highlighted the fact that both modern genetically engineered (GE) crops and organic maize have incurred significant genetic modifications, but the organic agriculture movement remains firm against the use of GE crops, including in the case of accidental gene contamination. Moreover, McClintock's work on the maize Ac/Ds system has parallels in other biological systems, such as the incompatibility genes discovered in many angiosperm species that prevent successful pollination between plants that do not have compatible genes.