The small dark yellow oval shapes that you see around the outer perimeter are the phloem, they act like veins and are responsible for supplying nutrients to the Banana.
These phloem are edible and nutritious. Some people will even dry and smoke them for a phycoactive experience. I would maybe not reccomend this unless you have done some research on it and know what you're getting into.
Ever wonder why you've never seen a banana seed in your bananas? It's because they've been specially bred to be seedless triploids which have three gene sets instead of two. This makes them not grow mature seeds which are large and allows for maximization of the edible parts.
Steepshot