Final answer:
The zygote is the plant structure formed by the union of a sperm and egg.
Step-by-step explanation:
The term that describes the plant structure formed by the union of a sperm and egg, which receives half of its chromosomes from the mother and half from the father is Zygote. The zygote is the first cell of a new organism and it represents the beginning of the development of a new plant. It contains a full set of chromosomes, half inherited from the mother and half from the father.
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