Final answer:
The form of the ovum that has a full set of chromosomes is called the zygote, which occurs when the sperm and egg combine during fertilization.
Step-by-step explanation:
The form of the ovum that has a full set of chromosomes is called the zygote. The sperm and egg each have only half the number of chromosomes as other cells in the body, making them haploid.
However, when they combine during fertilization, they form a diploid zygote with the full number of chromosomes.