Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
Put these events in the right order, and explain the link between the second and the third: the ovule becomes a seed; pollen lands on the stigma; the male gamete joins the egg; the pollen tube grows down the style; the zygote forms an embryo.
The stamens (anther and filament) are the male parts and make pollen. The carpel (stigma, style and ovary) is the female part, with ovules in the ovary. Pollination brings pollen to the stigma, a pollen tube reaches the ovule, and fertilisation makes a zygote. The ovule becomes the seed and the ovary the fruit.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The order. Pollen lands on the stigma; the pollen tube grows down the style; the male gamete joins the egg; the zygote forms an embryo; the ovule becomes a seed.
Step 2. The link. The pollen tube carries the male gamete through the style to the ovule. Without it, the gamete could not reach the egg.
Answer: pollination, pollen tube, fertilisation, embryo, seed; the tube delivers the male gamete for fertilisation.
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