Final answer:
Egg cells have an X chromosome, while sperm cells can have either an X or Y chromosome. Egg cells are larger and do not have a tail like sperm cells.
Step-by-step explanation:
Egg and sperm cells are different in several ways. Firstly, egg cells have an X chromosome, whereas sperm cells can have either an X or Y chromosome. This is because egg cells always carry an X chromosome, while sperm cells can carry either an X or Y chromosome, which determines the sex of the offspring. Additionally, egg cells are much larger than sperm cells and do not have a tail like sperm cells do.