4.2 Energy Transfer, Food Production & Nutrient Cycles Flashcards
What is a biotic component?
A living organism; producers, consumers, saprobionts.
What is an ecosystem?
A natural unit made up of organisms and their interactions with each other + the components (non living) of the habitat
What is an abiotic component?
The physical, non living aspects of the environment such as light, pH, water and CO2
What is biomass?
The total dry mass of organisms
How do we determine biomass?
Heat the plant material, record the mass, repeat until a constant mass is obtained and all water is removed
Why is sunlight conversion to energy low in efficiency?
Light misses the chloroplasts/chlorophyll
Some light is reflected
Light is the wrong wavelength
Why is energy transfer efficiency between trophic levels low?
Heat energy is lost during respiration
Parts of organisms cannot be digested
Loss by excretory products
Equation for efficiency of energy transfer?
Energy avaliable after transfer OVER
Energy avaliable before transfer
X100
=….%
What is Gross Primary Productivity? (GPP)/ Gross Photosynthesis
The total amount of light energy converted to chemical energy in photosynthesis
AKA
how productive photosynthesis is
What js Net Primary Productivity?(NPP) /Net Photosynthesis
The amount of energy from photosynthesis which remains available to primary consumers
How do we find NPP?
NPP= GPP - (R)
(R)= respiratory loss
Why do we need nitrogen in plants?
Essential for the production of amino acids and nucleotides.
What is nitrification?
The oxidation of ammonia and ammonium ions into nitrites and then nitrates by nitrifying bacteria.
How do nitrifying bacteria help plants?
They oxidise the ammonium ions in soil into nitrites and nitrates so that the plant can absorb them by active transport for protein synthesis.
What is ammonification?
The production of ammonia from organic compounds.
