Why do sunflowers always towards the Sun?

During growth, sunflowers need to absorb more sunlight to synthesize nutrients, so theflowers are always facing the sun. But after flowering, they are no longer orientedtoward the sun again.

Visually, the sunflower as a large flower, but really it's because hundreds of flowerchildren created. Flowers small to fall to seed. The small flowers will bloom on the outside first, so the growth of particles occurs in the long run, the flowers inside thehatch, sometimes they just for floaters.

Vitamin-rich sunflower seeds and vegetable oils, which are used to extract edible oils,junk food, animal feed.