Question: what is the genetic difference between sperm and egg?
Answer: One set of 23 comes from mom and the other 23 from dad. The egg and sperm cells are an exception--they have only 23 chromosomes each. A sperm from the man combines with a woman's egg in her womb to make a zygote. The zygote ends up with a total of 46 chromosomes and can now grow into a baby.