Barbara McClintock discovered mobile elements in corn by analyzing the genetic behavior of two elements, Ds and Ac. The interplay between these two elements has become one of the most interesting stories of discovery in the field of genetics. How do Ds
and Ac interact?
A) Ds causes a deletion next to the insertion site of Ac.
B) Ac causes a deletion next to the insertion site of Ds.
C) While Ds moves only if Ac is present in the genome, Ac is capable of autonomous movement.
D) Both elements can move only within chromosome 9.
E) The movement of Ac is dependent on two forms of Ds.
Answer: C
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