Seeds

Tiny things, these, and while not ugly in any way, they're not particularly attractive either. Which doesn't seem to make any difference to them doing their job.
Which is to propagate or reproduce the plant that hosts them. Technically speaking, it's the fruit of the plant that hosts them. Hundreds of them inside every fruit on the plant.
The fruit here is the capsicum, or to some, the bell pepper.
Comes in many different shapes (or different variations on a basic, characteristic shape), colours (or colors, to some), levels of heat (chillis at the hot end), and even sizes (from tiny, to as big as a rockmelon [or cantaloupe to some]).
Although capsicums come in a range of different sizes, the size of the seeds seems to stay about the same. Some seeds produce very small capsicums, other similar sized seeds produce ones 10, 20, maybe 40 times bigger.
On one hand, size matters; on the other, it doesn't.