system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5: How does Bamboo grow so quickly and why?

I’ve heard stories about being able to watch Bamboo grow, but how does it grow so quickly and why?
gpt
Plants need sunlight to create energy. The process of photosynthesis turns sunlight into sugar and that sugar fuels the energy the plants lives off. The stuff a plant takes from the soil doesn't provide it with energy but it does provide it with building blocks to grow.

That's why plants grow upwards. They absorb building blocks from the soil using their roots. And then they grow bigger to catch more sunlight and taller to try and outcompete the plants around them. After all, it's better to catch sunlight and throw shade than it is to be in someone else's shade.

Bamboo tends to grow in dense forests there is not a lot of sunlight that reaches the forest floor. So bamboo evolved to put all of its efforts into growing tall as fast as possible to break through the undergrowth and get to that sunlight.

It's also why bamboo grows in thin tall poles. It wastes no energy growing thick, it puts all its effort into growing tall.