One of my projects this Autumn and Winter is to grow corn inside. So far, I've got some lovely 6-8" shoots in my dining room. I've been using a 50 watt LED grow light in a floor lamp 14-16 hours each day. It isn't a great light, but it will work for what I'm doing.
You'll notice my shoots all lean in one direction. They're all leaning toward the grow light, which sits to the right of the planter. This is a great example of phototropism. Phototropism is the plant's tendency to grow toward a light source. It is a survival mechanism to help the plant get as much light as possible to make photosynthesis happen.
The fact that my corn is exhibiting phototropism means that photosynthesis is happening. My shoots are also a nice green, as they should be. And after weeding back the extra shoots, I can say my corn is going to have some nice, deep, sturdy roots. We're well on our way to a good harvest.