Final answer:
A gamete is a specialized sex cell that carries half the number of chromosomes. During fertilization, the chromosomes in a sperm combine with the chromosomes in an oocyte to form a zygote.
Step-by-step explanation:
A gamete is a specialized sex cell that carries half the number of chromosomes compared to body cells. In humans, the male gamete is called a sperm and the female gamete is called an oocyte. During fertilization, the chromosomes in one sperm combine with the chromosomes in one oocyte to form a zygote.
For example, when a sperm and an oocyte unite, the resulting zygote will have a complete set of chromosomes and will develop into a new individual.