The nitrogen cycle is essential for the survival of living organisms on our planet. Most nitrogen is contained in the Earth's atmosphere, and living organisms need a way to access that nitrogen. We will follow the cycle to understand how this happens.

How can plants be grown during cold seasons? Inside a greenhouse it stays nice and warm even if there are snowmen outside. Learn how Earth is like a giant greenhouse in this lesson.

Learn about global warming, what this term means, and how it manifests in the environment. Discover how the Earth stays warm and what causes global warming. Finally, explore how global warming affects different plants and animals.