Answer – The union of sperm and egg is called fertilization.
Explanation:
Midway through the menstrual cycle, a mature egg (one that can be fertilized) makes its way from the ovary into the fallopian tube. It remains here for about 12–24 hours. During this time, if semen enters the vagina through copulation, sperm cells swim up through the cervix.
Within six days, only some of these sperm cells make their way into the fallopian tubes with the uterus aiding their movement. If the mature egg is also moving through the tubes at the same time, one of the sperm cells may merge with it. This fusion of the sperm with the egg is called fertilization. It begins with the membranes of the sperm and egg combining, which further allows hereditary material to move from one cell to the other. The resulting cell thus formed is known as a zygote.
