The entire process takes 6 months (literally) because of how they go about animating the episodes. The shows are mostly drawn by hand. South park however uses computers which, in turn, allows them to do everything in 5 days. So what the Simpsons does is they prepare a whole season 6-8 months ahead of time.
Transitions lenses contain special patented photochromic dyes that cause the lens to activate, or darken, when exposed to ultraviolet rays from sunlight. When the UV light diminishes, the lenses fade back. As light conditions change, the level of tint adjusts, offering the right tint at the right time.
Bananas do not grow on trees. Rather, they grow from a root structure that produces an above ground stem. The plant is specifically classified as an arborescent (tree-like) perennial herb; in fact, it is the largest herbaceous flowering plant. The banana plant being an herb is that the banana itself is a berry.