The answer explains the stages of a plant's lifecycle, types of cross-pollination, and gymnosperms' fruit substitution.
Gametophyte Stage and Sporophyte Stage: Plants have two main stages in their lifecycle - the gametophyte stage where male and female gametes are produced, and the sporophyte stage which develops from the zygote. In angiosperms, male gametophytes develop in the microsporangium and female gametophytes in the megasporangium.
Types of Pollination: The two primary types of cross-pollination are self-incompatibility, where a plant's stigma rejects its own pollen, and dichogamy, where the male and female reproductive organs mature at different times to prevent self-pollination.
Gymnosperms and Fruit Substitution: Gymnosperms replace fruits with structures like cones or seeds. They lack structures like fruits as gymnosperms do not undergo the process of double fertilization seen in angiosperms.
https://brainly.com/question/22899994