I'm always fascinated by the ways different plants reproduce. I think the first flower that I ever took interest in was the rose. I noticed that as soon as it was pollinated, the petals would drop off, and shortly after, the ovary of the flower would swell and become persimmon colored rose hips.
Sunflowers are especially cool because it's a giant flower with thousands of mini flowers (florets) within it. Under each floret is a developing sunflower seed. Here are some pictures of it.
Remember to 'share' and spread the love of nature!