Figure 14.19 At what stage does the diploid zygote form?

1. When the female cone begins to bud from the tree
2. When the sperm nucleus and the egg nucleus fuse
3. When the seeds drop from the tree
4. When the pollen tube begins to grow

Figure 14.26 If a flower lacked a megasporangium, what type of gamete would it not be able to form? If it lacked a microsporangium, what type of gamete would not form?