Cycles and Energy Flow Flashcards
Define environment
The surroundings or conditions in which a person, animal, or plant lives or operates.
Define ecosystem
A biological community of interacting organisms and their physical environment.
Define abiotic factors
Non-living features of the environment.
Define biotic factors
Living features of the environment.
Define “both of these factors are interdependent”
They are dependent on one another and are also affected by one another.
Define biogeochemical cycles
A pathway by which a chemical element or molecules moves through the biotic and abiotic compartments of the earth.
Provide examples of biogeochemical cycles
The hydrological cycle, the carbon cycle and the nitrogen cycle.
Provide a similarity between energy and matter or mass
Like energy in an ecosystem, matter or mass in the form of nutrients moves through all organisms at each trophic level.
Define Law of Conservation of Mass
Mass is never created or destroyed.
Explain hydrological cycle
The hydrological cycle is consistently travelling. The water from the soil and the surface of bodies of water evaporates from the sun’s heat. Part of the water originates from transpiration. The water vapour is then carried by the wind. If the vapour ascends high in the atmosphere, it might form clouds or precipitation due to it being so cold. Sometimes, rainwater seeps into the Earth becoming groundwater. Once the water returns back to the bodies of water, this cycle restarts.
Define transpiration
The exhalation of water vapour through the stomata.
Define evaporation
The process of turning from liquid into gas.
Define condensation
Water which collects as droplets on a cold surface when humid air is in contact with it.
Opposite of condensation is …….
Evaporation
Define precipitation
Any product of the condensation of atmospheric water vapour that falls under gravitational pull from clouds.
Define infiltration
The process by which water on the ground surface enters the soil
Define surface run-off
The flow of water occurring on the ground surface when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil.
How much water on the Earth does the ocean contain?
98% is in the saltwater of the oceans
Location of remaining 2%
Of the remaining two per cent, some is found in the form of atmospheric water vapour and as permanent ice deposits in Greenland and Antarctica. Less than one per cent is available as freshwater to the organisms that live on the Earth.
Importance of hydrological cycle
It is only because water is recycled that life on our planet has been able to exist for millions of years.
Only source of energy in water cycle is ……..
The Sun
Importance of sun
The sun essentially provides energy for all living organisms.
Define carbon cycle
The movement of carbon atoms between the living and the non-living environment
Examples of carbon’s existence
Carbon dioxide gas in the atmosphere, fossil fuels, organic matter, dead organisms, pollution and in the ocean.
Basic element of organic compounds is ……
Carbon
Is carbon present in both dead and living organisms?
It is found in all living things and in all things that once lived but have since died.
Importance of carbon dioxide for green plants
Green plants need carbon dioxide to carry out photosynthesis, the process by which they produce glucose.
How is carbon absorbed?
Land-based plants absorb the carbon dioxide they need from the atmosphere through tiny pores in their leaves.
Methods of distributing carbon atoms among organisms in an ecosystem
Photosynthesis and digestion distribute carbon atoms among the organisms within an ecosystem.
Define respiration process
The carbon in glucose is released back into the atmosphere as carbon dioxide
Word equation for respiration in plants
glucose + oxygen → carbon dioxide + water + heat energy
Biggest pool of nitrogen location
78% of nitrogen located in the atmosphere
Nitrogen element symbol
N
Nitrogen chemical formula
N2
Appearance of Nitrogen
Colourless and Odourless gas
Provide an example of nitrogen importance
Nitrogen plays an essential part in the formation of amino acids and nucleic acids.
Name of Process that allows nitrogen to be used by living organisms
Nitrogen fixation
When does nitrogen fixation occur?
Mostly in lightning strikes
How do lightning strikes do this?
The electrical energy from a storm converts atmospheric nitrogen into various useful nitrogen compounds.
What is the difference between nitrites and nitrates?
Nitrites are NO2 while nitrates are NO3
How are nitrates used?
These dissolve in rain droplets and fall onto the Earth’s surface to be taken up by the roots of plants. Once inside the plant, they are converted to amino acids and nucleic acids. These nitrogen compounds are then consumed by animals when the plants are eaten. The animals now have a source of nitrogen from which they can produce their own proteins and nucleic acids.
How is nitrogen returned to the ecosystem?
Nitrogen is returned to the ecosystem as ammonia (chemical formula NH3), present in urine and faeces, or when dead organic matter decomposes. This ammonia is converted back into nitrates by nitrifying bacteria that are naturally present in the soil. Another type of bacteria, the denitrifying bacteria, converts these nitrates back into atmospheric nitrogen gas.
What are heterotrophs?
An organism that cannot produce its own food, instead taking nutrition from other sources of organic carbon, mainly plant or animal matter. Examples include zebras, humans, worms, etc.
What are autotrophs?
These are the organisms that can prepare their own food from simple substances like carbon dioxide and water.
What do food chains show?
The flow of energy through ecosystems.
Define food web
The interrelationship between many food chains
Define decomposers
Organisms that use the organic matter of dead plants and animals
How do decomposers decompose plants and animals?
They release digestive enzymes to break down organic matter and then absorb the products of digestion.
What do decomposers recycle?
They recycle the matter, materials and elements such as carbon, nitrogen, phosphorous, etc, that would otherwise stay locked in the remains of dead organisms forever
What do decomposers not recycle?
Energy
Examples of decomposers
Fungi and bacteria
What does energy pyramid show?
It shows the total energy in trophic levels and how that energy is lost along a food chain.
How much energy is lost at each trophic level?
At each level energy is lost – usually around 90%.
Describe the appearance of energy pyramids
The base of the pyramid represents the energy contained in producers. The next level shows the energy contained in 1st order consumers and so on.
What gives a pyramid steeper sides?
Greater trophic efficiency
Define human impacts
Any human activities which have a negative effect, either directly or indirectly, on either the biotic or abiotic components of an environment.
Define greenhouse effect
The rise in temperature that the earth experiences when certain gases in the atmosphere trap heat energy from the sun.
Purpose of greenhouse gases
They trap heat consequently warming the planet
What is a greenhouse?
A greenhouse is a small glass house used to grow plants.
Why is it named the greenhouse effect?
The glass which the greenhouse is made of allows light to enter and prevents heat from escaping, making it very warm inside. The heat allows the plants to grow in winter. A similar effect is happening to Earth.
Example of greenhouse gases
Water vapour, carbon dioxide, nitrous oxide and methane
What type of radiation is emitted from the earth’s surface?
Infrared radiation
How is CO2 produced?
Carbon dioxide (CO2) is released in large quantities from natural processes including respiration by living organisms, volcanoes and forest fires. Man-made CO2 emissions are released into the atmosphere via power stations, motor vehicles and factory emissions.The majority of CO2 emissions in Australia arise from the combustion of fossil fuels. The largest single contributor to CO2 emissions is electricity generation (which relies mainly on coal), followed by road transport.
Provide examples of human activities that are warming our planet
Burning of fossil fuels (major contributor ) Deforestation Factory emissions Transport emissions Electrical appliances Population growth: indirect cause Some farming practices
Define introduced species
Foreign species which have arrived accidentally or been introduced intentionally by humans.
What are introduced species also called?
Feral or invasive species
Why are they bad?
They compete with native flora and fauna in their environment.
Define amino acids
The building blocks of protein
Define nucleic acids
The building blocks of genetic material
Define biodiversity
The variety of plants and animals and other living things in a particular area or region
Define competitors
Organisms that require the same resources from the same habitat.
Define conservation
Preservation of natural resources for future generations.
Define consumer in biology
Organisms that obtain energy from consuming other organisms.
Define cycle
Repeated sequence of events
Define ecology
Study of the relations of organisms to one another and to their surroundings.
Define predator
An organism that kills and eats other animals
Define producer
Organisms that make their own food using carbon dioxide, water and sunlight through photosynthesis, also known as an autotroph.
Define prey
An organism that is used as food.
Define sustainable
Not being harmful to the environment or depleting natural resources, and therefore supporting long-term ecological balance.
Define nitrifying bacteria
Nitrifying bacteria convert the most reduced form of soil nitrogen, ammonia, into its most oxidized form, nitrate
Define ammonification
The process of converting natural nitrogen compounds into ammonia.
Define nitrification
The process by which ammonia is converted into nitrites and nitrates.
Define denitrifying bacteria
Microorganisms whose action results in the conversion of nitrates in soil to free atmospheric nitrogen.
Why is nitrogen important to plants?
Plants require it to grow
What does the arrowhead in food chains and food webs mean?
Arrowhead shows where energy is transferred not what eats what
Difference between primary, secondary and tertiary consumer?
Primary consumers are herbivores, while secondary consumers are carnivores that feeds only upon herbivores while tertiary consumers are carnivores at the topmost level in a food chain that feeds on other carnivores.
