Life on Planet Earth Section 2.1 Flashcards
How far is the Earth from the Sun on average?
149,597,890 km
Earth travels through space at what speed?
107, 229 km/h
Is the Earth perfectly round?
The earth isn’t perfectly round, it is slightly flattened at the north and south poles.
How old is the earth?
Scientists have the dated the Earth as being between 4 and 5 billion years old!
Earth is mostly made up of..
Earth is mostly iron, oxygen and silicon
_____ % of the Earth’s surface is covered in water
70%
The Earth’s atmosphere extends out to ________km
10,000 km
The atmosphere is made up of…..
78% nitrogen,
21% oxygen
[ less than ] <1% argon, water vapour, carbon dioxide and other gases
the atmosphere acts like a…
Acts like a blanket and moderates surface temperatures.
the atmosphere blocks out..
Blocks solar radiation (UV light)
the atmosphere contains..
Made up of the troposphere (closest to Earth’s surface), stratosphere and mesosphere.
Lithosphere
Earth’s outer layer, the rocky shell of Earth
The mountains, ocean floors and rest of Earth’s solid landscape.
Ranges from 50 to 150 km in thickness
Hydrosphere
Made up of all the water on Earth
Solid - glaciers
Liquid – lakes, oceans, etc and groundwater
Gas – clouds, water vapour
97% of Earth’s water is contained in the _____
97% of Earth’s water is contained in the oceans.
Biosphere
The zone around Earth where life can exist
Most can be found on land and in water
Some micro-organisms can live several kms below the earth’s surface
Can have artificial biospheres
