earth science Flashcards
(22 cards)
what are the layers of the earth in order?
crust
mantel
outer core
inner core
how does the density of the layers change (most to least)?
inner core
outer core
mantel
crust
what is the crust like?
the rocky, outer layer
what is the mantel like?
the semi-solid middle layer
what is the outer core like?
liquid iron + nickel, generates earth’s magnetic field
what is the inner core like?
solid iron + nickel
what is the percentage composition of each gas that makes up earth’s atmosphere?
78% nitrogen
21% oxygen
1% argon
how does respiration affect the atmosphere?
it releases carbon dioxide into the atmosphere
how does photosynthesis affect the atmosphere?
it pulls carbon dioxide out of the atmosphere
how does combustion affect the atmosphere?
it releases carbon dioxide into the atmosphere
how has the atmosphere changed over time?
over time oxygen levels increased and carbon dioxide levels decreased, water vapour condensed to form oceans
what is the role of carbon dioxide in the atmosphere?
needed in photosynthesis + produced in respiration
what is the role of oxygen in the atmosphere?
produced in photosynthesis + needed in respiration
why is a balance of carbon dioxide important in the environment?
to prevent global warming
what is climate change?
a long-term shift in the earth’s conditions due to C0₂
what are some consequences of climate change?
rising sea level
melting ice caps
habitat loss
how is crude oil formed?
millions of years ago, many microscopic animals fell to the bottom of the sea and were buried under sediment. After lots of pressure was applied they changed into crude oil, which moved up to permeable rock and is now drilled up.
what is crude oil?
a mixture of compounds containing mainly hydrogen and carbon
how is crude oil used?
fuel + heating
how does combustion of fossil fuels lead to global warming?
it releases greenhouse gases that trap heat in the atmosphere
define extinction
when no living members of the species are present
why might conserving species be of benefit to the environment and humanity?
They provide essential resources such as food, medicine, and raw materials
