Topic 6 - Ecological Energetics Flashcards
What is the food chain
The sequence of organisms, with each being a food source for the next
What is the difference between a grazing and detritus food chain
A grazing food chain starts with living plants
A detritus food chain starts with dead organic matter
What are producers
The autotrophic plants produce food through photosynthesis and ultimately support all other levels
What are consumers
Primary consumers feed on producers, secondary producers feed on primary consumers, tertiary consumers feed on secondary consumers
What are decomposers
Decomposers and detritivores feed on the accumulated debris of dead organic matter
What are the three pyramid relationships
Pyramid of numbers
Pyramid of Biomass
Pyramid of energy
What does a pyramid of numbers represent
The total numbers of the organism at each tropic level in an ecosystem
What are some disadvantages of a pyramid of numbers
It is difficult to determine what represents a single individual
The approach does not take into account the size of an organism
What does a pyramid of biomass represent
The total biomass of the organisms at each tropic level in an ecosystem
What is a disadvantage of a Pyramid of Biomass
You would need to gain dry mass, meaning you would have to kill animals
What does a pyramid of energy represent
The energy value of a new material produced at each tropic level over time
What are some reasons for solar energy never reaching the ground
It is reflected back into space
It is absorbed by the atmosphere
Why is most solar energy not used in the plant
Most energy is reflected by the leaf
Some is transmitted through the leaf
The wavelengths that hit the chloroplasts cannot be used
The reactions are inefficient
What are some reasons for the reduction in energy at progressive tropic levels
Some of the material is not consumed
Some of the material is not digested
Some of the material ends up as a waste product
Many of the materials are used in respiration
In plant growth, how can productivity be increased
Use of fertilisers, and pesticides
