Apple has published a new series of videos in celebration of Earth Day that both highlight the company’s green energy efforts and explain some of the science behind clean energy today. The video series includes comical illustrations and narrations from Apple execs including VP Lisa Jackson.

Each video poses a question and features an Apple employee explaining the company’s environmental strategy:

Do solar farms feed yaks?

Can we produce zero waste?

Why does Apple make its own sweat?

Can a building breathe?

In addition to the new video series, Apple has shared a lofty goal of making all of its products from recycled material at some point in the future. Apple is also hosting an Apple Watch Activity Challenge for Earth Day on Saturday that encourages customers to go outside and exercise for 30 minutes to unlock special Earth Day iMessage stickers.

Check out the full video series below: