I absolutely love growing plants in my courtyard. It's to the extent that I can barely walk around the area. There are vines sprawling all over the yard right now. One of my favorite plants from this growing season was my mammoth sunflowers. Some of these things grew up to 14 feet tall or so, well above the eaves of my roof! The best part, of course, were the flower heads that were more than a foot across.
Each sunflower disk is comprised of hundreds and hundreds of tiny flowers, also called florets. The collection of which make up what we consider to be a single flower. In the image above you can see dozens of disk florets, these are the flowers that become pollinated and produce seeds.
The second type of floret in a sunflower disk are all along the edge, they're called ray florets. Each ray floret has a single yellow petal. Ray florets are what give the sunflower their distinct appearance.
Plants have a tendency to follow a few specific rules that dictate how they grow. One of those rules is presented as a golden spiral. Seeds of a sunflower disk appear to spiral from the outside of the disk towards its center. The spiral swirls both clock-wise and counter clock-wise.
During my time in art school there were always those dreaded 3 hour critique sessions during the photography classes. As soon as you walked in the room that day you would scramble to claim the "best" wall space. My criteria for the "best" space was determined by when I thought that part of the wall would be discussed. Did I want to just get the crit over with first thing, or drag on my torture...