DENDROLOGY

Detailed explanation-1: -The male gametophyte lands on the female cone, forming a pollen tube through which the generative cell travels to meet the female gametophyte. One of the two sperm cells released by the generative cell fuses with the egg, forming a diploid zygote that divides to form the embryo.

Detailed explanation-2: -Cones are the reproductive structures of the conifers: Cones are diploid tissue produced by the dominant sporophyte stage. The haploid gametophyte stage develops and produces gametes inside the cone.

Detailed explanation-3: -In the male cones, or staminate cones, the microsporocytes undergo meiosis and the resultant haploid microspores give rise to male gametophytes or “pollen grains” by mitosis. Each pollen grain consists of just a few haploid cells enclosed in a tough wall reinforced with sporopollenin.

Detailed explanation-4: -In conifers, fertilization takes place when pollen from male gamete-producing cones is transferred to female gamete-producing cones, usually by the wind but occasionally by plants and animals transferring the pollen. When the pollen fertilizes the female cones, the seeds begin to develop.