Module 6 Section 6: Ecosystems Flashcards
What is a habitat
The place where an organism lives, e.g. a rocky shore or a field.
What is a population
All the organisms of one species in a habitat.
What is a producer
An organism that produces organic molecules using sunlight energy, e.g. plants
What is a consumer
An organism that eats other organisms, e.g. animals and birds.
What is a decomposer
An organism that breaks down dead or undigested organic material, e.g. bacteria and fungi.
What is a trophic level
A stage in a food chain occupied by a particular group of organisms, e.g. producers are the first trophic level in a food chain.
What is an ecosystem
All the biotic (living factors) and abiotic factors (non living factors) in a certain area
Examples of biotic factors
Food
Space (territory)
Breeding partners
Examples of abiotic factors
Light
Affects plants as light is needed for photosynthesis
Greater availability of light the greater the success of plant species
Temperature
Effects enzymes controlling metabolic reactions
Plants and ectothermic animals develop rapidly in warmer temperatures
Changing temperature (from seasons) can trigger migration or hibernation
Water availability
Lack of water leads to water stress which can cause death
Water stress will cause plants to wilt and reduce photosynthesis levels
Oxygen availability
Warm, slow flowing water leads to a drop in oxygen concentration
Lack of oxygen leads to suffocation of aquatic organism
Water logging also decrease amount of oxygen in soil leading to plant suffocation
Edaphic (soil)
Different soil types with different sized particles
Clay (small fine particles which are easily waterlogged), loam (mixed of sizes of particles which retains water but doesn’t waterlog), sandy (coarse, spaced out particles which doesn’t retain water but is easily eroded)
How can population size be affected by changes in an ecosystem
Cyclic changes: predator prey relationships, seasonal changes, day and night cycle, tides
Directional changes: climate change, deposition in rivers, erosion of a coastline
Unpredictable/erratic changes: natural disasters, lightning
Pattern of how species performance and intensity of abiotic factors
Includes factors such as temperature and pH
When may the pattern of abiotic factors and species performance not follow the bell curve
What is biomass
Mass of living material in a particular place
What is living material
Carbon containing material
How does energy mainly enter an ecosystem
Enters by photosynthesis where plants convert sunlight energy into a form that can be used by other organisms
Plants are called producers and store energy as biomass
Another word for energy transfer in ecosystems
Can also be called biomass transfer in ecosystems
How is energy transferred in ecosystems
When organisms eat other organisms
Producers are eaten by primary consumers, primary consumers are then eaten by secondary consumers and secondary consumers are eaten by tertiary consumers.
How can energy transfer be shown with diagrams
Food chains show simple lines of energy transfer
Food webs show lots of food chains in an ecosystem and how they overlap
When may energy be unable to be transferred and how is energy recycled back into the ecosystem
Energy can be locked up in the things that can’t be eaten (e.g. bones, faeces)
Gets recycled back into the ecosystem by decomposers.
How much energy is lost through tropic levels
About 90%
Why may large amounts of energy not be taken into producers or consumers in the first place
Around 60% is never taken in by organisms
Plants can’t use all the light energy that reaches their leaves
e.g. some is the wrong wavelength, some is reflected, and some passes straight through the leaves.
Some sunlight can’t be used because it hits parts of the plant that can’t photosynthesise
e.g. the bark of a tree.
Some parts of food, e.g. roots or bones, aren’t eaten by organisms so the energy isn’t taken in
Some parts of tood are indigestible so pass through organisms and come out as waste, e.g. faeces
These pass to decomposers