Question on: SS3 Biology - Development Of New Seeds

Pollen grains are the male gametophytes in flowering plants. They consist of a tough outer layer called the exine and a delicate inner layer known as the intine. The exine is composed of sporopollenin, making it resistant to environmental factors. Within the pollen grain, there are two haploid cells: the generative cell and the tube cell. The generative cell divides to form two sperm cells.