1. Life in the Earth System
Chapter 15

2. The biosphere is the part of the Earth where life exists.

3. The hydrosphere is all of the Earth’s water regardless of the state of matter (solid, liquid, gas).

4. The atmosphere is the blanket of air surrounding a planet’s surface.

5. The geosphere represents the Earth’s surface features such as the continents, rocks, and the sea floor.

6. The Gaia hypothesis proposes that Earth is a kind of living organism with the different spheres interacting with each other.

8. The canopy is the uppermost branches of the trees
The canopy is the uppermost branches of the trees. It prevents most of the sunlight from reaching the forest floor.

9. A grassland is an area where the primary plant life is grass
A grassland is an area where the primary plant life is grass. Two general kinds – 1) tropical grasslands 2) temperate grasslands.

10. Tropical grasslands (savannahs) receive very little rainfall
Tropical grasslands (savannahs) receive very little rainfall. Animals here have adapted to shifting levels of moisture.

11. Temperate grasslands receive much more rainfall.

12. Desert biomes receive very little rainfall (less than 10 inches per year). They are very arid.

13. Deciduous trees have adapted to winter temperatures by going dormant during the cold season.

14. Temperate Deciduous Forest are characterized by hot summers and cold winters. Dominant plant species include oak, maple, and beeches.

15. Coniferous Trees retain their needles all year round.

16. Temperate rain forests are characterized by having one long wet season and a relatively dry summer. Evergreen conifers dominate this biome.