The ovum, a mature egg cell released by the ovaries of the fertile female approximately every 28 days, is the largest human cell; whereas sperm, incidentally, is the smallest.
For conception to take place, a mature egg cell must be at the right place at the right time. Conception takes place when a sperm penetrates the egg cell before it reaches the uterus and fertilizes it within 24 hours of its release, then the two cells combine into one.
All of the 400,000 egg cells a woman will ever produce are already present in her ovaries when she is born, although the eggs are in an undeveloped form. That means that the egg that would become you was as old as your mother at the time you were conceived.
“I’m frightened of eggs, worse than frightened, they revolt me.”
– Alfred Hitchcock