Carbon cycle

Question 1

Why is carbon vital to the environment?

Answer 1

component for all major organic molecules present in living organisms such as fats, carbohydrates + proteins.

Main source of carbon for land-living organisms = atmosphere

Question 2

In which ways are carbon-containing compounds utilised in producers?

Answer 2

CO2 converted into small carbon-containing organic molecules by photosynthesis in plants
+ other photosynthetic organisms.

Used in production of macromolecules (carbs, proteins, lipids)

Question 3

In which ways are carbon-containing compounds utilised in consumers:

Answer 3

Carbon macromolecules passed from producers into primary consumers when producers are eaten.

Passed up food chain when consumer consumed.

Question 4

In which ways are carbon-containing compounds utilised in decomposers:

Answer 4

Organisms die –> carbon compounds released through decomposition

Carbon released into atmosphere as CO2 when decomposers respire

Dead organic matter accumulates in areas where decomposers not present.

(bottom of oceans/bogs).
–> Carbon becomes ‘trapped’

=fossil fuels

Question 5

How is carbon removed from the atmosphere?

Answer 5

Dissolved in seas + oceans
–> provide major source of inorganic carbon for plants.

Formation of limestone –> carbon eventually returned when rock weathers

Question 6

Why are there fluctuation in atmospheric carbon dioxide?

Answer 6

Photosynthesis = requires light

Respiration = throughout day + night
–> CO2 released at relatively constant rate into atmosphere

.: Atmospheric CO2 levels night > day

Question 7

Why has global atmospheric CO2 levels increased significantly in more recent times?

Answer 7

Combustion of fossil fuels: releases C02 trapped in fossil fuels

Deforestation: removed significant quantities of photosynthesising biomass from earth –> less CO2 removed.

Question 8

Describe how CO2 is a greenhouse gas?

Answer 8

Increased levels of atmospheric CO2 traps more thermal energy in atmosphere

–> production through human activities contributing to global warming.

Question 9

How does temperature affect the amount of CO2 dissolved in oceans?

Answer 9

Higher temp = less gas dissolved

.: Global warming reduces carbon bank in oceans and releases more CO2 into atmosphere