Unit 12 #2 - Ecosystems Flashcards
(37 cards)
List populational levels in order
population, species, community, ecosystem, biosphere
Every populational level is an emergent property of the level below it or above it?
Below it
*emergent properties: properties found in the whole but not in individuals alone (the whole is greater than the sum of the parts)
What does genetics explain
how chemicals are organised into a living
organism, and how this information is transmitted.
What does evolution explain
how selection operates on genetic
variation within populations, so that populations adapt to the
biotic and abiotic elements of their environments
it is seen in genes, populations, species and communities
What does ecology explain
how the environment is determined by the
interactions between its living and non-living components.
Name an exmaple of geological phenomenon created and maintained by a living ecosystem
Soil
In fact, some cliffs are formed of crushed shells of mollusks
What is an ecosystem
Interaction between a community (biotic) and abiotic factors in the environment
Name 2 things an ecosystem needs and how they relate to one another
- Energy: solar (photoautotrophs) or chemical (chemoautotrophs), it enters from space and leaves by heat radiation though the food chain
- Matter : N, P, C, H2O…, it cannot enter or leave earth so it circulates through biochemical cycles
Link between both: energy is needed, ultimately from the sun to move matter around and transform it
What are the 2 laws of thermodynamics and their link to chemical transformations of life processes involving energy transfer?
1st law: energy cant be created or destroyed
2nd law: total entropy of universe must increase
there is flow of energy from sun to earth to space as heat
This is because energy is used to organize matter in an open system, but heat is lost at each energy transfer because of 2nd law
How does lavoisier’s principle apply to matter
Conservation of mass: matter on earth stays on earth (closed system)
In a food web, what does the arrow point
the consumer (from the consumed)
The arrow shows energy flow
What is biomass and its main component
The total mass of organisms in a given volume or area
Its main component is carbon (ie we have lots of carbon)
What is productivity
the amount and rate of production
which occur in a given ecosystem
over a given time period.
It is either dry matter or energy produced per area per time.
What is the difference between primary and secondary productivity
Primary productivity: biomass of autotrophs produced
Secondary productivity: biomass of heterotrophs produced
What is the percent loss of energy from solar energy to heat
99%, so 1% to primary producers
What is the percent energy transferred from one trophic level to the next
10%
How do zooplankton and phytoplankton relate
zooplanktons are heterotrophs that eat phytoplankton, a photoautotrophs
detritivores
eat dead organic matter
Decomposers
break down non-living organic molecules to smaller molecules: take carbs., nucleic acids, lipids, proteins and breaks them down into CO2, CH4, NH3
How are pyramids of energy flow, biomass and numbers alike
all have first-level carnivores on top , but fewer, and shows that organisms are being eaten as fast as they are being produced (biomass=numbers)
What is the difference between a top-down trophic cascade and a bottom-up trophic cascade
A bottom-up trophic cascade can happen if the primary producers
are eliminated or greatly reduced ie draves killed aquatic vegetation
Biomagnification
subsatnces such as pesticides and mercury stored in tissues get concentarted in tissues of animals up the food chain becasue they eat all the pther animals that have fewer conenctrations within them ie belugas st-lawrence lots of mercury
Does microplastics biomagnify
No, but the toxins they absorb do! The microplastics are ingested by animals in water
Anthropocene
current geological age seen in segmentation rocks that is more compressed
