5B Flashcards
what is primary productivity
the rate at which producers convert light energy into chemical energy
what is Gross Primary Productivity (GPP)
the rate at which chemical energy is converted into carbohydrates
what is net primary productivity (NPP)
the rate at which energy is stored in plant biomass
what will happen to 90% of the energy stored in glucose
it will be released from glucose to create ATP for the plant and it wont be passed on to primary consumers
what is the equation required to calculate the ecological productivity
NPP = GPP - R
how to calculate the efficiency of energy transfer
net productivity/energy transferred * 100
how to calculate the efficiency of biomass transfer
biomass transferred / biomass intake * 100
define habitat
the place where an organism lives
define population
all of the individuals living in a habitat
define community
multiple of populations living and interacting in the same area
define ecosystem
community and its interaction with non-living organisms in it habitat
what are biotic factors
living factors that affect population within their community, biotic factors come about a result of activity of other organisms e.g. predation, food availability and disease
what are abiotic factors
non-living factors that effect their population within their community e.g. light intensity and wavelength, temperature and oxygen or carbon dioxide concentration
how does light affect the the community
light is used for photosynthesis as light increases the rate of photosynthesis increases
define the term niche
the role of a species within its habitat
define the term abundance
the number of individuals of a particular specie living in a habitat
why do food chains usually have fewer than five trophic level
biomass transfers are not 100% efficient so there is not enough energy to support five levels
define the term distribution
where a species live
how does niche accounts for the distribution and abundance of an organism
niche in abundance: if two species occupy similar niche they will be competing, their population will decrease therefore their abundance will be lower
niche in distribution: when a specie is not well suited for the biotic and abiotic factor of a habitat they will move therefore their distribution will decrease
what are the two different types of sampling
random: the sampling point are selected at random which avoids bias which would affect the results
systematic: the sampling points are located at a fixed intervals at sampling site this avoids missing out sections of habitat and allow investigating the effect of environmental features on species distribution
when is a random sampling site is the best and how sites can be selected
when the sampling area is reasonably uniform and can be selected by:
-laying out a grid over the area to be studied
-generating random number co-ordinate
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how to determine the abundance and the distribution of a species
- frame and quadrats
- line and belt transect
what is a frame quadrat
a square frame to study the distribution of a sessile organisms and have different sizes
what does a dynamic ecosystem mean
they are constantly changing
define the term succession
the process of ecosystem change over time which the biotic and abiotic conditions change
what is primary succession
is the process that occurs when newly formed or exposed land inhabited by an increasing number of species
what are the stages of primary succession
- pioneer species land on exposed rock and begin to grow and can withstand harsh conditions
- as pioneer species die and decompose they form organic soils
- seeds of small plant land and begin to grow
- the roots of the small plants helps the soil form being washed away
- as the small plants die and decompose the soil becomes more rich in nutrients therefore larger plants will grow. the final species that colonise the new land become the dominant species of the complex ecosystem
what is a climax community
the final community formed
why do the biotic and abiotic factor factors change at each succession stage
so that the environment can become more suitable for the species that have not colonised the land yet and often they colonise in such a way that it becomes less suitable for the previous species
what is the difference between secondary and primary succession
at secondary succession the soil is already present so the process begins at a later stage
how do human activities affect the climax communities and the process of succession
they prevent or interrupt the succession and stops teh climax community from developing. plagioclimax are stable but would not have without human
what are the evidence for climate change
- records of atmospheric carbon dioxide levels
- records of average global temperatures
- records of changing plant communities gained from sampling of pollen grains preserved in peat overtime
- records of tree growth
what is dendrochronology
the record of tree growth by analysing the rings in the trunks of trees
What is a plagioclimax
The climax stage of a community, influenced by humans or some other factors
what is a greenhouse gas and what is their effect
its a gas that absorbs the re-radiated radiation and traps the radiation to reduce heat loss to the space and this effect is known as the greenhouse effect
what is a anthropogenic climate change
the increasing levels of carbon dioxide and methane (the changing climate) as a result of human activities
what causes anthropogenic climate change (carbon dioxide)
- volcanic eruptions and the weathering of limestone rocks
- combustion of fossil fuels which release carbon dioxide
- releasing of carbon dioxide by damaging carbon sinks ( trees, peat bogs, soil and the oceans)
there is a clear correlation between carbon dioxide levels and increasing global temperature but its not a causation
what causes anthropogenic climate change (methane)
- the intensive framing of animals by the release methane from the gut of ruminant animals
- land fill sites which release methane by the decomposition of food waste
- Extraction of fossil fuels from underground releases methane
-Anaerobic bacteria release methane - the warming of poles releasing methane
how is carbon transferred in the carbon cycle
- carbon dioxide is found in the biomass of an organism
- carbon is transferred when one organism consumes and digests other
- carbon is found in the atmosphere as carbon dioxide and in the oceans
state the events of the carbon cycle
- carbon is present in the atmosphere in the form of carbon dioxide
- producers remove carbon dioxide from the atmosphere and add to their biomass as carbohydrates by photosynthesis
- carbon is transferred from and to consumers by feeding
- carbon is transferred into atmosphere by plants and animals as a result of respiration
- carbon dioxide can be removed from atmosphere by dissolving into the oceans which can be taken by plants in the ocean
- when living organisms die their tissues are broken down by decomposers such as fungi which also respire and release carbon dioxide
- any living organism that is not fully decomposed can go towards the formation of peat or fossil fuels
- combustion of fossil fuels releases carbon dioxide into the atmosphere
how to reduce the levels of carbon dioxide
- reduce the combustion of fossil fuels
- reducing the combustion of biomass
- reducing the disturbance of carbon pools
- increase the rate of photosynthesis by planting trees
what are extrapolated data used for
- to make predictions about global temperatures in the future
- to produce models that show how the climate may change in the future
what can global warming prediction be used for
- plan for future
- encourage people to change their activities
How does increased atmospheric warning have an impact on climate patterns
- weather events become more extreme
- water availability in some habitats is changing
- seasenol cycles are changing
- polar ice and glacires are retreating
- sea levels have been rising faster in recent years
Define biomass
The dry mass of all living organisms in an area
How do lower temperature prevent reactions from proceeding or slow them down
- molecules will move slowly as they have less kinetic energy
- since they have less kinetic energy the rate of successful collisions between the substrate and the active site of enzyme will decrease
- substrate and enzyme collide with low energy so making it less likely to form or break a bond
How do higher temperatures speed up the reaction
- molecules move more quickly as they have more kinetic energy
- increased kinetic energy results in more successful colissions between the active site of enzyme and substrate which leads to more enzyme-substrate complex formation
- substrate and enzyme collide with more energy which would make it more likely for bonds to form
what would happen if an enzyme continues to pass a certain temp.
the rate at which an enzyme catalyzes a reaction drops sharply as the enzyme begins to denature
- the increased kinetic energy and vibration of an enzyme weakens the hydrogen and ionic bond that hold the enzyme molecule
- the breaking of bond causes the tertiary structure of the enzyme to change
- the active site is permanently and its shape is no longer complementary to the substrate
what is a temperature coefficient Q10
calculates the increase in rate of reaction when the temperature is increased by 10
how to calculate Q10
rate at higher temperature/ rate at lower temperature
how does enzyme activity affect living organisms
-some chemical reactions take place faster at higher temperature ex. photosynthesis produces foods for producers and and other organisms which relies on the function of enzymes like rubisco
- some chemical reaction are slowed down at higher temperatures
- the sex of young inside the egg is determined by temperature
- species may have to change their distribution in response to survive higher temperature
define the term evolution
changes in the heritable characteristics of living organisms over generation
how are heritable characteristics determined
there are changes that not inherited ex. plants have leaves eaten do not lead evolution
- the alleles of genes that are present in an individual
- alleles may change as a result of mutation causing them to become more or less advantageous
- heritable characteristics that are advantageous are most likely to be passed on
define natural selection
the process by which organisms that are better adapted to their environment survive, reproduce and pass on their advantageous alleles causing advantageous characteristics frequency to increase within a population
what are the steps of natural selection
- variation between different individuals within a population which results in different in DNA base sequences from different sources: mutation, meiosis, random fertilization during sexual reproduction
- environmental factors that affect survival chances which is said to be selection pressure
- due to variation some individuals will adapt better for the survival in the face of selection pressure
- individuals that are well adapted to their environment will make to adulthood and reproduce more offsprings and individuals that can’t survive the environment will produce fewer offsprings
What are endemic species
A species is found in only one area
what is the unit for primary productivity
kjm^-2yr^-1
