APES U1 (frq collegeboard)

the possible unit 1 FRQ from collegeboard

Describe a biological process by which carbon is removed from the atmosphere and converted to organic molecules.

Photosynthesis: the process by which plants take in carbon dioxide from the atmosphere and convert it into food/glucose/sugar/complex carbohydrates; plants fix carbon into food/glucose/sugar/complex carbohydrates.

Describe a biological process by which carbon is converted from organic molecules to a gas and returned to the atmosphere.

Decomposition of organic material by bacteria OR fungi converts organic carbon into gases such as methane

Oceans and terrestrial systems are also important carbon reservoirs. (i) Explain how atmospheric carbon is incorporated into two oceanic sinks.

1. Carbon can be taken up by organisms like phytoplankton for photosynthesis
   2. Carbon can react with other elements/compounds and form carbonates/limestone/sedimentary rocks

Identify one terrestrial sink, other than fossil fuels, that stores carbon for thousands to millions of years.

Trapped/incorporated into ice caps/glaciers
Limestone or sedimentary rocks

The burning of fossil fuels has been shown to increase the concentration of carbon in the atmosphere. Discuss TWO other human activities that increase the concentration of carbon in the atmosphere.

Deforestation reduces carbon reservoirs. • Raising cows and/or other ruminant animals releases carbon-containing gases (methane)

Identify an environmental problem that results from elevated atmospheric carbon concentrations. Discuss one consequence of the problem you identified.

Global warming-> melting ice caps; habitat destruction

Phosphorus is another element important to all organisms. (i) Describe one major way in which the phosphorus cycle differs from the carbon cycle

Phosphorus cycle has no gaseous phase

Identify one reason that phosphorus is necessary for organisms

needed for dna and rna's sugar-phosphate backbone