Across
- 3. A deciduous forest is a biome dominated by deciduous trees which lose their leaves seasonally.
- 5. the envelope of gases surrounding the earth or another planet.
- 7. a vast, flat, treeless Arctic region of Europe, Asia, and North America in which the subsoil is permanently frozen.
- 8. the variety of life in the world or in a particular habitat or ecosystem.
- 9. the strength and vitality required for sustained physical or mental activity.
- 12. the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a byproduct.
Down
- 1. a green pigment, present in all green plants and in cyanobacteria, responsible for the absorption of light to provide energy for photosynthesis. Its molecule contains a magnesium atom held in a porphyrin ring.
- 2. a colorless, odorless, highly flammable gas, the chemical element of atomic number 1.
- 4. radiant energy emitted by the sun.
- 6. (of electromagnetic radiation) having a wavelength just greater than that of the red end of the visible light spectrum but less than that of microwaves. Infrared radiation has a wavelength from about 800 nm to 1 mm, and is emitted particularly by heated objects.
- 7. the arrangement of the natural and artificial physical features of an area.
- 10. Matter is anything that takes up space and can be weighed.
- 11. the process or result of joining two or more things together to form a single entity.
- 13. the star around which the earth orbits.