Answer: Days to months (up to 12 months in some species) before fertilization occurs.
- A Just a few hours typically pass before fertilization is fully completed
- B Days to months (up to 12 months in some species) before fertilization occurs
- C Mainly a matter of seconds pass before the egg becomes fertilized
- D A fixed period of exactly two weeks occurs in every conifer species studied
Correct answer: B. Days to months (up to 12 months in some species) before fertilization occurs
Explanation: Conifers: after wind pollination, pollen tube grows slowly through female gametophyte tissue. In Pinus, this takes ~12 months. The tube eventually delivers sperm cells to the archegonium for fertilization.
Double fertilisation in angiosperms: one male gamete fuses with the egg to form the diploid zygote (syngamy), while the second fuses with the two polar nuclei to form the triploid primary endosperm nucleus (triple fusion). Image: Triploid, CC BY 3.0, via Wikimedia Commons.
Concept context
Flower structure, pollination, double fertilization, and seed/fruit development - the highest-scoring Class 12 biology chapter in NEET.
Read the full Sexual Reproduction in Flowering Plants notes →