I believe the answer is this:
DNA replication is called semi-conservative because half of the original double-helix appears in one daughter strand formed in replication if you need any more help then please comment and let me know ok. :)
Sperm cells inside the pollen grain travel down the pollen tube and into the ovary which contains the ovules. Fertilization occurs when one of the sperm cells fuses with the egg inside of an ovule