Functioning Ecosystems

Question 1

What is the competitive exclusion principle?

Answer 1

The competitive exclusion principle states that two species occupying the same niche cannot coexist.

Question 2

What is an example of the competitive exclusion principle?

Answer 2

Red Squirrels and grey squirrels

Question 3

How does solar energy transfer and transform into biomass?

Answer 3

Solar energy from the sun is is transformed into chemical energy through photosynthesis. This chemical energy provides useable energy in autotrophs for essential processes including metabolism and growth. This means that through this energy biomass is produced as autotrophs grow and reproduce. Furthermore, biomass is transferred through trophic levels as higher levels consume the lower ones and gain a percentage of their biomass (Around 10-20%)

Question 4

How can solar energy be lost through the food chain?

Answer 4

-Radiation (at night)
-Reflection (by atmosphere)
-Absorption (by Earth)

Question 5

How is energy transferred through the food chain?

Answer 5

Biomass transfer

Question 6

Gross vs net productivity

Answer 6

Gross primary production is the amount of chemical energy as biomass that a producer creates in a given length of time whereas net primary production is the amount of chemical energy that is not consumed by respiration. (Gross-respiration)

Question 7

Describe the water cycle.

Answer 7

Water is cycled through the environment changing states through the following processes:
-Evaporation
-Evapotranspiration
-Condensation
-Rainfall
-etc

Question 8

Describe the carbon cycle.

Answer 8

The carbon cycle is the movement of carbon through the biotic and abiotic environment. It involves the transfer and transformation of carbon as an atmospheric gas, oceanic carbonate (bicarbonate in water or calcium carbonate in carbonate based organisms), organic materials (carbohydrates, lipids and proteins) and as non-living remains (detritus and fossils)

Question 9

Describe the nitrogen cycle.

Answer 9

-Nitrogen gas in the atmosphere must be chemically processed by nitrogen fixing bacteria to be used by plants.
-Plants absorb nitrogen from the soil as nitrate ions while animals consume it from plants
-When organisms die the nitrogen goes through ammonification to return to its inorganic form
-Nitrogen in the soil is converted back to a gas through denitrifying bacteria

Question 10

What is a niche?

Answer 10

The role of an organism in an ecosystem, its habitat, feeding relationships and its interactions with other species and the biotic and abiotic factors within the ecosystem.

Question 11

What is a keystone species?

Answer 11

A keystone species is a species that has a disproportionately large effect on its natural environment relative to its abundance. It plays a major role in the balance of the ecosystem.

Question 12

What are some of the processes that transfer or transform carbon?

Answer 12

-Photosynthesis (carbon from atm to biosphere, carbon, hydrogen and oxygen make glucose)
-Respiration carbon dioxide is released into environment by converting glucose and oxygen into heat, ATP and carbon dioxide
-Feeding, carbon moved through food chain
-Decomposition/ sedimentation, animal remains become sediment, trapping carbon and converting it into rock layers
-Fossilisation, fossil fuels when burned release carbon dioxide into atmosphere
-Combustion, combustion reactions produce carbon dioxide