The Outside World
Guys, there's this place called "Outside", and it's just out your front door! Only problem is, you can't turn off the light, it sorta slowly turns itself on and off. Also, there are animals and plants outside, so that's pretty cool too.
Plants are Different, Too!
There are several dividing factors on plants, but let's talk about a major one: Vascular and Non-Vascular plants. Vascular plants have 2 types of tissues (Xylem and Pholem) that are similar to veins in our bodies, but Non-Vascular plants don't have these, simply getting nutrients from the environment.
While we're at it, let's talk about the Non-Native Species. These guys are from other countries, and compete with the local wildlife for food. Things like Kudzu can out-compete the natives, killing them off.