During fertilisation in humans, a sperm reaches the ovum in the ampullary region of the fallopian tube. Regarding the events that follow, which statement(s) is/are correct?

• Statement I: Entry of the sperm into the secondary oocyte induces it to complete its second meiotic division, which is unequal and forms a second polar body and a haploid ovum (ootid).
• Statement II: A sperm coming in contact with the zona pellucida layer of the ovum induces changes in the membrane that block the entry of additional sperms, ensuring that only one sperm fertilises an ovum.